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Gerber Viper Toilet Review 2024 (Collection Guide & Specs)

The Viper collection could be a great match for someone looking for something on a budget. Not only does it handle waste well according to MaP, but it also consumes smaller amount of water when compared to 1.6 GPF models. We've analyzed its most important features below to help you better understand what it's capable of.

Alternatively, you can learn more about the Gerber brand here.

Our pick

Gerber Viper TB-20-562

The TB-20-562 is a gravity fed, high efficiency toilet, that utilizes low volumes of water (1.28 gallons) to clean the bowl. According to their site, this is WaterSense certified (EPA's water protection standards), and will help your bathroom save up to 20% more water than 1.6 gallon units. This naturally means you can save money on your water bills too. Our calculator can help you understand this better. It may not seem like much, but over the course of its lifetime, it may even help you save the amount it cost you to buy it. That's assuming that it lasts a decade or longer, which they're designed to.

If your after something with a quiet refill, the fluidmaster helps with this. It's also equipped with a three inch flush valve to let more water through the bowl, improving performance and power. This gravity based system enables it to achieve a 800g MaP rating.

A 9 1/4" by 6 1/8" water surface area and glazed 2" trap passageway help it move larger quantities of waste without blocking, staining, or streaking the surface. A large water spot also combats odors and stops them lingering or rising.

It's two piece design adds a couple of extra steps while installing it. But it fits a twelve inch rough and comes with a elongated bowl which has its advantages, especially in helping users stay comfortable when sitting down on the seat.

Overall, it's a lower budget model, but still contains the functionality inside to handle day to day usage without being too wasteful. Externally, it's not the most aesthetically pleasing design, but all things considered, we like it.

Other things to consider

Bowl clearance - If you've no other option but to squeeze what you can into a tight space, you need to ensure their is appropriate amount off clearance either side of your bowl. 15 inches minimum. The same applies to the front, but you need to leave 21 or 24 inches depending on the plumbing code.

If you've got very little floor space, how do you get around this? A sensible way forward would be to find something with a low profile. You can compare product dimensions for this. Round bowls are usually the most compact bowl shape so that's a good place to start. Alternatively, you can use our depth guides here: 24-25 inch depth and 26 inch depth. Both of these are shorter than average and protrude the least from the wall, giving you more leg room.

Rough in - You may be familiar with the term rough in as it's an important part of the installation process and something that manufacturers make clear in their product descriptions. This is the distance from a finished wall (with no baseboard), to the center of your set flange. Learn how to measure yours here. After you've measured yours, we have several helpful articles to help you determine which toilet matches your requirements. You can read them here, and here. You'll find a helpful insight into specific sizes and more.

MaP ratings - How efective is the flush? It's common sense to want to know more about the flushing mechanism and how powerful it is. Fortunately, there is industry testing in place that can help with this. One of the popular ones is Maximum Performance. This is a company that assigns individual products a score based on how many grams of waste a toilet can handle without getting blocked. Some would argue anything above 500 grams on this scale is fluff and for show only. Others are happy to stick with units that score highly on this scale. We recommend you choose products that have at least a 500 grams score. The great thing about the TB-20-562 above is that it's 800 grams. Right up there with the market leaders.


The Viper toilet is a great all in one solution in two senses. One, all the parts are included, no need to purchase the fixtures separately. And two, from a flushing performance point of view, it's an all rounder. Its strong rinsing action coupled with water efficiency proves that. It still has some drawbacks, like the fact that it's not ADA compliant or chair height. But if your happy with a standard or traditional bowl size, then you can take a lot of positives from its specifications.