Buying a toilet

How to Buy a Toilet – Toilet Buying Guide


Learn How to Buy a Toilet in 5 Minutes – First Time Buyer’s Guide

How to Buy a Toilet

How to Buy a Toilet

‘How To’ articles on how to choose the right toilet for your home are all over the web. The reason you are here is obvious. You are not too familiar with what toilet types are there in the market place.

So you want to learn what is the best toilet to buy within your budget. Or you could be remodeling or building a new toilet but space is a constraint. So you want to know what is the best toilet for small spaces.

Whatever your reason is, this ‘How to Buy a Toilet’ article will fill you in. So let’s spare you another one of those ‘How To’ articles that only scratches the surface.

Let’s Get Started

In a nutshell, you just want a toilet that gives you the least problem. You want it to be efficient, clean, saves you money and pleasing to look at. And not forgetting comfort.

You know, the toilet is the place of relief and not a pain in the rear (no pun here). And it’s the only place in the world that you can be ‘Me’ for a little while.

So how to buy a toilet? You ask. That’s a fair enough question considering there are thousands of toilet types out there. To look for the right toilet that meet your needs and budget requires a little research.

Here’s some great tips on how to buy a toilet. Hopefully it can provide some pointers to help you find the right toilet for your home, in 5 minutes.

First Thing First – Determining the Toilet Minimum Space

This is the most important first step you shouldn’t skip. But if you are just replacing your existing toilet, you may want to skip this step.

Knowing the area size you have for a toilet will save you time and money from hunting down the wrong toilet. So first thing first, you need to know the minimum space required for a toilet installation.

If you live in an apartment with a small bathroom, then a compact size toilet will be a good start.

This minimum space requirement is important. So that you will have the space not just for comfort and safety, but also for maintenance purpose.

Just imagine when it clogged, or you need to replace the toilet flange for a running problem. You will thank the Almighty for the precious space you have to handle those situations.

And, you could be running in with the law as there are State regulations to what is the minimum space required for a toilet.

So how do you work out the minimum space for your toilet, and what is a good size toilet to fit in?

Clearance Space Is Gold

When you are remodeling or planning for your new bathroom, look at the clearance space first. The space around your toilet must meet the minimum as lay out by your local building code for bathroom.

Start with the distance from the back wall where your toilet sits against, to the front. And the distance between side walls and sanitary fixtures, observe the minimum distance.

Different States will have different clearance distance. So where ever you live, check the local building code for bathroom design and layout.

As a rule of thumb, measure from the center of the toilet bowl to the side wall or sanitary fixtures. Keep a minimum distance of at least 15 inches on both side of the toilet. And this is the minimum distance you should adhere to.

Of course you can have more than 15 inches if you have the luxury of space available. But for a more pleasant toilet space, the recommended distance is 18 inches to begin with.

So try to allocate a wall to wall spacing (left to right) of 36 inches, otherwise the minimum is 30 inches wide.

The front space area, or the ‘Clear Zone’ should be at least 21 inches away from the front tip of the toilet bowl.

Again, for ease of movement go for 24 inches or more. Also take note to allow some space for door opening if your toilet is just next to the door.

Minimum Clearance Space

Diagram 1.1 – Minimum Space Clearance

Choosing the Right Toilet Size

Once you have gotten the space you need for your toilet, the next step you’ll learn is how to choose the right toilet.

But first, you must know the rough-in size.

What is rough-in size?

The most important specification of a toilet is the rough-in size. In toilet language, rough-in size is like a shape matching game. Get it wrong, your toilet won’t fit.

Rough-in size is the distance from the back wall to the center of the sewer outlet. That is the hole on the floor where your waste material gets flush away. (see diagram below).

So the trapway outlet (the hole at the base of your toilet) must sit precisely on the sewer outlet. Otherwise, you will find clogging and leakage happen every so often that life is just so hard to get by.

The rough-in should be measured from the wall and not from any baseboard or molding. So make sure you measure from above the baseboard or molding to get an accurate measurement of the rough-in.

Get Your Rough-In Right

There are 3 rough-in sizes – 10 inches, 12 inches and 14 inches. If you are replacing your toilet, you need to know the rough-in size to buy the right toilet that fit.

If you are planning for a new build or a remodel, always plan for the 12 inch rough-in. That’s the most common of the 3 rough-in sizes. You will find that you won’t be lack of choices when you are shopping for a toilet.

And finding a replacement is easy because all toilet manufacturers will have the 12 inch rough-in for all its toilet models. You are almost a toilet expert if you know how to measure the rough-in size.

How to measure rough-in

Diagram 1.2 – Measuring the Rough-in

Assuming you are planning for a new bathroom and space is a little squeeze, you may consider a 10 inch rough-in. it’ll save you a few inches on the depth with a compact toilet.

And if the space is really small and challenging, consider a wall hung toilet. Which can easily save you about 9 inches of depth. Here’s a review on wall hung toilet from TOTO.

Toilet Dimension

Diagram 1.3 – Dimension of a Compact Toilet (American Standard)

Measuring A Toilet

It doesn’t matter if it’s 10 inch or 12 inch on the rough-in, elongated or round front toilet. You should look at the distance from the wall, where the toilet is backed against, to the front tip of the toilet bowl (the depth).

Usually there will be a gap between the wall and the back of the toilet. The gap can be between 0.5″ to 1.25″ depending on the manufacturer’s specification. You should include the gap distance when taking measurement for the depth.

You will then have an idea of how much space you have as the Clear Zone, and whether you have met the minimum distance rule.

The rest of the measurements are the width and height of the toilet (see Diagram 1.3).

The toilet seat height is another consideration you should focus on. If there is a family member who has a special need, then go for the ADA models. They are higher on the seating (chair height) to help with easier access and comfort.

Let The Shopping Begin

Now that you have all the measurement information in hand, the rest of ‘how to buy a toilet’ is just shopping fun. You will now be looking at features, color, shapes and aesthetic. Limited only by how much your dollar could stretch.

So what to look for when buying a toilet?

It’s a matter of how you are going to prioritize your needs. If you have spent a chunk on your bathroom design, you are most unlikely to compromise on aesthetic. So that might weight over features a little.

And aesthetic is a subjective matter, as it lies in the eyes of the beholder.

Toilet companies like TOTO, American Standard and KOHLER have an impressive range of well designed toilets. They are both great looking and packed full of cool features, even if you are on a small budget.

Which Flush Toilet Can Really Flush?

Let’s talk about the most talk-about function of the toilet – The Flush.

Be it a single or dual flush toilet, there are basically 2 flushing systems the world is using – The Siphonic Flush and the Washdown Flush toilet.

Let’s not get into the details of the two flushing system here. But you can tell them apart quickly with their characteristics.

Siphonic Flush

(1) Large Water Surface Area – Typically around 8″ x 7″.
With a large water surface area your waste is submerged in water all the time. And bowl streaking is less likely to happen.

Also odor is down to the least as water acts as a filter to prevent smell from filling the air while you are doing your business.

(2) Long And Narrow Trapway
TrapwayThe trapway diameter is typically about 2 inches wide and shape like an inverted ‘U’ or ‘S’ shape. This long trapway is for creating the siphon action during a flush.

And a typical problem with siphonic toilets is it’s narrow trapway. It is prone to clog.

(3) Quieter Flush
Generally siphonic flushing produces less noise compared to the washdown system.

The water gushing down from the tank is quickly met with the suction force when the siphon action begin. The waste and water in the bowl get suck down through the trapway and into the drainage pipe.

Usually there’s the swirl and ‘pull’ during a flush.

Washdown Flush

(1) Small Water Surface Area – Generally about 51/2” x 4″. With this small surface area, most people find it hard to aim and bowl streaking is unavoidable.

When the load is heavy, the small water volume cannot contain all the waste. So there are always waste sticking to the bowl surface and out of the water. Needless to say, odor is a problem. You just have to endure the smell until you flush out.

Hopefully the odor has dissipated when the next person uses the toilet. So it’s better to have windows or install an exhaust fan for better ventilation.

(2) Bigger And Shorter Trapway
The flushing depends entirely on gravity and the weight of the water in the tank to flush out the waste. So the trapway has to be big enough to avoid congestion and allow the waste and water to be ‘pushed’ down the drain pipe.

The trapway is also made shorter so that all can be easily push down into the sewer pipe. And because of the short trapway, washdown toilets are shorter in length. This is good for small spaces with limited length.

And the most significant advantage of washdown toilets is it’s short and wide trapway. They are relatively clog free.

(3) Noisy Flush
As expected, it is a lot louder than the siphonic flush toilet. The amount of noise is like pouring a whole pail of water into the bowl. The noisy flush will last for almost 3 seconds, that’s when the tank has emptied. Then follow by the refilling noise immediately.

Don’t Go Against The Odds

In the United States, siphonic toilets take up the most shelf space in all the retail stores. Even online mega stores like Amazon or Home Depot, the best sellers are all siphonic models.

You will find that there isn’t much of variety for washdown toilets to choose from. But in Europe, more than 85% of toilets are washdown type.

Even though the washdown system are less likely to clog because of the shorter and bigger trapway. Americans by and large still prefer the siphonic toilets.

They typically don’t like the idea of small water spot in the bowl. As they find that with this small ‘target area’, bowl streaking or skid marks are bound to happen. And they hate that disgusting sight in the bowl.

Siphonic toilets are more efficient in waste removal. They can handle heavier loads better with one flush and produce low noise level. And if well maintain, siphonic toilets can be as clog-free as its wash-down counterpart.

If you live in the United States, it’s better to go for the siphonic toilets. Then you’ll find it’s easier to get replacement parts and accessories.

Wait! There’s One More Flush You Gotta Know.

Pressure-assisted Toilets

Don’t try this unless you have like 3 or 4 basketball teams in your family. Typically used in commercial properties, they are for heavy usage.

They flush like a space shutter taking off and leave no waste in the bowl, not even a trace. Powerful stuff and you can forget about privacy as everyone can hear you flush from a mile away.

The pressure-assisted flush is basically a tank-within-tank design. It uses water displacement to create air pressure that thrusts waste out forcefully through the trapway.

Though there are some installed in residential homes, they are mostly large families. Definitely not suitable for small apartments.

And if you need to have one, you got to make sure the water pressure in your home is at least 25 psi (pounds per square inch). Otherwise this power flush toilet will not work properly.

The good things about this pressure-assisted toilet are;

  • It has a higher water level in the bowl which keep solid waste submerge in water all the time.
  • The flush is powerful and efficient.
  • The sealed tank design eliminates sweating or condensation during humid weather.

The bad is of course the thunderous flushing noise it makes. And replacement parts aren’t that easily available compared to the regular flush toilets.

Water Saves The Day

Save your life too. Ask the Californians.

Due to a water regulation in 1994, residential toilets sold in the United States can only use up to 1.6 gallons of water per flush.

In 2004, EPA conceived the Watersense Program. Two years later it released its specification for tank-type HET (High Efficient Toilet). The intention is to encourage toilet manufacturers to redesign toilets to meet their specification.

If saving water is one of your priority, then look out for toilets with the the WaterSense sticker. These are High-Efficiency Toilets (HET) that use less than 1.6 gpf of water without compromising on performance. Otherwise, with the 1.6gpf cap you are still doing a little part for water conservation.

The WaterSense label is proof that a toilet has gone through a certification process. It has to meet all the stringent criteria for both efficiency and performance.

And to earn that recognition, it has to be certified by an independent test lab recognized by EPA.

Here are some of the best toilets to buy that carry the WaterSense label.


American Standard


Mesmerizing Toilet Bowl Shapes

Toilet Bowl Shapes
Over 90% of toilet bowls come in 2 shapes – elongated or round. Yes that’s kind of boring if you asked and sorry to disappoint.

You may have seen a rectangular shaped bowl, but looking for a replacement seat that fit can be a nightmare.

You will have to wait longer to replace one, because few would stock something that sell only once in a blue moon. Or prepare to pay over $100 for a toilet seat that’s only as close as it can get.

Of course if you have deeper pocket, nothing is in your way of getting what you want.

Guys using round front toiletRound bowls usually cost less and take up less space. And they are generally shorter than the elongated bowl by about 2 inches, measuring from front to back.

Unless you have a constraint on space, always go for the elongated bowl. Most guys just hate to have their proprietary body part touching the bowl rim especially on a round bowl.

Think of the power button icon… makes you wonder if this was coined by a guy while pooping on his round bowl toilet.

An elongated bowl provides better support and comfort. And since it is most people’s favorite, it will be easier to find a replacement seat. And they don’t cost you limbs to get one.

One-piece or Two-Piece Toilet – Not a Life Threatening Decision

One piece toilet vs two piece toilet

One piece good or Two piece better

Your next consideration is whether it should be a one-piece or two-piece toilet. Is it a matter of personal preference? Or do you prefer a toilet that’s easy to clean and nice to look at, or easy to replace and still pleasing to the eyes?

There are more to that. Here are some pros and cons of two piece and one piece toilet.

(Switch to Landscape view on mobile devices)

One Piece ToiletTwo Piece Toilet
Easy to cleanSince there is no joint between the bowl and tank, chances of dirt and bacteria accumulating are eliminated.Grime, mold and bacteria can build up at the joint between the tank and bowl, making it hard to thoroughly clean without removing the tank.
Tank LeakageOnly possibility is water from the tank leaking into the bowl.Water not only can leak into the bowl, it can leak out if the tank-bowl coupling is not properly made or due to poor maintenance.
Ease of InstallationCumbersome and heavy. But once secured to position, it’s 95% done because you don’t have to deal with the tank installation.Bowl and tank are installed separately, and each portions are easier to manage even for one person.
ReplacementIf the tank or bowl is broken, you have to replace the entire toilet.Tank and bowl can be replaced separately.
CostHigh (some models are in the under-$400 range)Matching feature to feature, most 2-piece toilets cost less than the 1-piece models.
PerformanceBoth 1-piece and 2-piece toilets are comparable in terms of service life and functionality


Wall Hung Or Wall Mounted Toilet – You’ll Love It

Wall hung or wall mounted toilets are great space saver if you have a really small bathroom to begin with. You can easily save about 9 inches of floor space, front to back. And they look way cooler than those floor mounted toilets.

The biggest takeaway of wall hung toilets is they are super easy to keep clean. Most people choose the wall hanging toilet mainly for this reason.

The best time to install a wall hung toilet is during remodeling or constructing a new bathroom.

If you are replacing your floor sitting model with a wall mounted toilet, it’s going to be messy. You will need to re-plumb the drain pipe from the floor to the wall. Besides plumbing, there will be hacking, plastering and tiling work need to carry out. It can be as good as remodeling your entire bathroom.

The Main Concern About Wall Hung Toilets

Space Saving Toilet

Image from

One important factor to consider is the weight limitation of wall hung toilets. If you have a family of heavy weights, you are better off with a floor mounted toilet.

Although it is getting popular among Americans, there is still concern of safety. And if you are concerned, please know that over 90% of toilets in Switzerland are wall hung.

If that’s not convincing enough, the American Society of Mechanical Engineers has a standard for wall hung toilets. So make sure the framework that holds the toilet conform to ASME A112.6.2.

The best wall hung toilet support system is Swiss made. The name is Geberit. The in-wall frame strength limit exceed that of ASME A112.6.2. and can support a weight of up to 880 lbs.

Here’s a TOTO wall hung toilet review which features the Geberit in-wall carrier system.

Despite the weight limitation, more and more homes are getting on with wall hung toilets.

Besides saving you some serious bathroom real estate, you will love the clean line appearance. And no more dragging yourself when it comes to toilet cleaning. It’s a breeze now.

Performance wise, wall hung toilets are comparable to the regular floor sitting models. When maintain well with proper use, wall hung toilets can last just as long as any best rated toilets out there.

Touchless Flush – Nice!

The toilet is the dirtiest place in any homes or commercial properties. If not well taken care of it can quickly become a breeding ground for harmful bacteria and germs.

And our hands are frequently in contact with many household items, including cutleries. Unknowingly, food may get contaminated and lead to food poisoning.

Washing your hands is not 100% fail-safe either. Most people don’t wash their hands thoroughly after using the toilet. More so when they did it in a haste, maybe to answer the door or a phone call.

Touchless Toilet

Touchless toilets can help eliminate the possibility of spreading diseases by contact.

Raise the level of hygiene in your home with a touchless flushing toilet. It won’t cost you much compare to a normal trip-lever or push-button flushing system.

In fact, you can even retrofit your existing toilet to a touch-less one for less than $100. And you don’t need to call a plumber as the installation is pretty intuitive.

Even better, make the seat touch-less as well. When you don’t need to use your hands to lift and close the seat cover. Hint: The popular TOTO Washlet S350e Toilet Seat (May cost more than the toilet itself but you will love it)

With the touchless flushing, there won’t be any compromise on the flushing performance. It uses a small motor which is mechanically connected to the flush valve, to activate the flush.

And it uses common household batteries for operation. So there’s no worry of a utility power failure.

Here’s a popular touchless flush kit from KOHLER.

Comfort Height Toilet – You Will Grow to Love It

Comfort height toilets are tall toilets. They are usually about 2 to 3 inches higher in sitting height than regular toilets.

A toilet with a seat height of 17 to 19 inches, including the toilet seat, is a comfort height toilet.

The bowl height of a regular toilet measures about 15 inches from the floor to the top of the toilet bowl rim. Whereas most comfort height toilets begin at 16″. The toilet seat will add another 1 to 2 inches to about 17 to 19 inches high.

Different manufacturer will have their own term for ‘comfort height’.

American Standard call it the Right Height, and TOTO terms it as Universal Height. They all mean the same comfort height toilets.

But not everyone appreciate such “comfort” when they are physically short. Or the lack of ‘knee height’ that causes them to sit with their feet dangling in the air.

One way around this situation is to use a step stool which will compensate for the lost height.

But do spare a thought for your elderly family members or someone who may have leg injuries or bad knees. They will appreciate the extra height that provides the convenience and comfort.

But the majority of users love these comfort height toilets. Simply because of the ease of sitting down and getting up.

You will grow to love these comfort height toilets as you age.

ADA Compliant Toilets

ADA stands for American with Disabilities Act.

The act is drawn in 1990 to protect the rights of people with disabilities to freely access public facilities and services.

When it comes to toilets, the main consideration is the sitting height requirement. Which should allow for maximum accessibility for people in wheelchairs or other disabilities.

To be ADA compliant, a toilet’s sitting height must be between 17″ to 19″ from the floor to the toilet seat top.

Hence an ADA toilet is also a comfort height toilet. But a comfort height toilet is not necessarily an ADA compliant toilet.

This is because manufacturers may intentionally design their toilets a little short of the required minimum 17″. And call it comfort height or right height toilet. The other obvious reason is to save on certification cost.

Whether it’s comfort height or ADA compliant, you should consider more than just the height for the disabled person. Such as providing more clearance space around the toilet. Install grab bars and even slip-proof floors if possible.

Especially for elderly folks, ample support is a must for ease and safety.

Here’s ADA Standards for Accessible Design if you are interested to know more.

The cost difference among the comfort height and ADA compliant toilet is minimal. If you have a need for a tall toilet, just go with the ADA model. You can’t go wrong with it.

Toilets with Concealed & Skirted Trapways

Skirted Toilet

One Piece Skirted Trapway Toilet – By Kohler Co.

The modern toilet is more than a functional device to help dispose of your waste, it is also designed to look good.

Skirted design or concealed trapway toilets look way cooler than those exposed types. Those exposed trapways are like the ugly varicose veins and it’s hard to clean.

If you plan to remodel your bathroom for a modern look, choose the skirted design.

The straight sides of the concealed trapway toilets make it hard to trap dirt and easier to keep clean. But, they are more costly than the traditional models. Probably because of the extra china that’s needed to hide the trapway.

But rest assured, the cost difference won’t hurt your wallet.

Want an even better looking toilet? Pay a little more and get a one-piece and skirted toilet for your prize bathroom.

Who Should Install Your Toilet?

Probably by now you have decided on what toilet to buy, it’s time to think of how you are going to install it.

Installing a toilet can be fun (for some). It can be challenging to do it yourself for the first time, so you might want to watch a tutorial on how to install a toilet.

You can find a DIY video on Youtube which will guide you on. Otherwise hire a plumber to do the work for you when you aren’t that sure if you are up to it. Especially if you have decided on a wall hung model.

Communication Is Key To A Successful Toilet Installation

If you are going to hire a plumber, it helps to communicate with your plumber on the toilet type and model. So that he knows what to expect and prepare the necessary materials before arriving at your home.

Then the work process can be a lot smoother and nobody gets frustrated.

You may have read in forums or blogs about some bad user’s experience with their plumbers. And the less-than-acceptable work produced. Usually it’s due to poor communication between the users and their plumbers.

Or that they just leave their plumbers to figure their way around with the installation. This often leads to some improvise work that don’t follow the manufacturer’s installation protocol. When problem arises, warranty can be a really nasty issue.

Every new toilet will have an installation manual included.

You can send a copy to your plumber in advance, or send them the URL of the installation video by the manufacturer. All the established manufacturers have good installation videos, so send them to your plumbers.

And it’s also a good idea to watch it yourself so you know and understand the whole installation process. Maybe you might even find it’s easy enough to do it yourself, and save a few hundred bucks as a result.

Before you start the installation, be it doing it yourself or by a plumber, make sure you check the local building code first. Ask your plumber about the local building code and you can also judge how competent he is from there.

A well prepared installation is key to a full functioning and trouble free toilet. Remember that.

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Buying a toilet can be fun and getting the right one is all that matters.

You begin by knowing the space area that you have. Then get the right rough-in size, follow by where and how to install the toilet according to your plan. After which you are on your way to shop for the best toilet that suits your needs and budget.

You have learned the 2 types of flushing system. You should know now what is a good flushing system for you. And not forgetting the replacement parts which must be easily available.

Then you might want to cut down your monthly water bills by going for a water saving toilet.

A dual flush toilet with a half flush that uses 1 gpf (gallon per flush) and a full flush 1.6 gpf is a good start. Better still, get one with the WaterSense label which has been tested and certified by a professional test lab.

If space allows, get an elongated toilet which is comfortable and offers better support. Also the replacement parts are easy to get.

Otherwise the round front toilet can save you some space, or a wall hung toilet to save even more floor space. And always go for the 12 inches rough-in if condition allows.

Want your toilet to be clean and hygienic always? Then a touchless flush and seat are sure to improve the hygiene of your home by a few notches.

For more comfort, consider the comfort height or ADA compliant toilet.

Whether you are replacing a toilet, remodeling or a new build, go for a skirted design toilet. It’ll liven up your bathroom with a modern look, besides being easy to clean.

And to further simplify cleaning, you should consider the 1-piece toilet with concealed trapway.


Installing a toilet requires a little planning. If you are a handy person, and doesn’t mind getting your hands dirty, try do it yourself. And save some money from hiring a plumber.

Otherwise there’s always the option to get help from a skilled local plumber. And remember to communicate with your plumber before the actual installation. That will avoid unnecessary hiccups and risk of an improper installation.

Have you learned how to buy a toilet? You may have a point to add or discuss, just Leave a Comment below.

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  1. Very informative and helpful. Thank you.

    Just a quick question: Can a syphon replace the plugged wash down flush unit in my tank? The pedestal toilet definately dosen’t have that “u” or “s” bend though. Just considering a cheap way to boost the flush power only for solid waste. My landlord won’t let me replace the toilet and I thought this might clear heavy loads in one flush and save water. But, I don’t want to contravene any laws or regulations. Is this allowed? Or will it not work because the pan doesn’t have the “s” bend? Its a low level, not close coupled, so it has a short flush pipe. Am also considering getting an old vintage high level tank, (if possible) if that won’t work. The extra gravity might make a difference. But not sure if a refit of these vintage tanks is allowed. Or perhaps I don’t as a diyer have to stick to all the same regulations a plumber or builder would, not sure. Any guidance and/or suggestions appreciated.

    1. Author

      Hi Simon.

      The regulation only states that the flush volume should not exceed 1.6 GPF. And in States like California, the maximum allowable flush volume is 1.28 GPF. Other than that the usual plumbing code applies to the draining and piping system which you have no authority over. So you’ve got to leave them as it is.

      Now, if you want to modify the tank to give it a more powerful flush, the things you need to deal with is how you can fit the new tank to the existing bowl. This will be a challenge that I have no clear answers for you. It depends on your creativity. You will have to find hardware or invent some to adapt. The high level tank is a good idea which I think you can do with the right piping size and gasket/seal to make sure no leaks. Also you may need to adapt the water supply too. I see lots of trial and error to be expected here. Will you try? I’ll be keen to know how and what you’ve done. 🙂


  2. very informative. I learnt a lot.

    1. Author

      @Thommo Thanks 🙂

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