Repair when Not in Use
Determining Whether You Have a 2" or 3" Flush Valve and Flapper
One of the biggest challenges is finding the right flapper for your toilet. Most toilets will have a 2-inch drain or a 3-inch drain. Fluidmaster manufactures a standard or universal size of flush valves with flappers and are among the most common flush valves to be used. Although there are many different types of flush valves, most flush valves are interchangeable and depend on the size of the ceramic flush hole that is bored through the tank by the porcelain manufacturer.
Fluidmaster’s Flush Valves use flappers to connect to the flush valve and can be easily replaced by snapping them off and on to the flush valve. These flappers are labeled as 2″ or 3″ for their corresponding flush valve size to make it easier for you to select the correct flapper.
The simplest way to determine which Fluidmaster flush valve and flapper to use is to measure the flapper that is already on the flush valve. To identify what size is needed, measure the width of the flapper from end to end. If the flapper measures 3 inches across, select a 2″ flapper (like the 502 Fluidmaster model). If the flapper measures 4″ across, then select a 3″ flapper (like the 5403 Fluidmaster model).
The 507AK – 2″ Flush Valve comes with the 2″ 502 Flapper:
The 540AKR – 3′ Flush Valve comes with the 3″ 5403 Flapper:
Our newest flapper is the 523A Super Flapper. This is the ONLY toilet flapper that replaces both 2″ and 3″ flappers. To learn more about this flapper, click here: Super Flapper
To solve ALL your toilet problems, consider the Everything Kit.
Download our free guide to fix common toilet problems: Fluidmaster Toilet Repair Guide
Frequently Asked Questions
