Fluidmaster K-400H-043 Fill Valve + 2" & 3" Super Flapper

The Fluidmaster Universal PerforMAX fill valve + 2” & 3” Super Flapper is the newest kit with the most technologically advanced universal toilet flapper and fill valve on the market. This 2-Piece kit is the best solution to fix noisy, running toilets. It takes all the guess work and uncertainty out of deciding what pieces or sizes of flappers to buy to fix your toilet.

This kit includes our most powerful toilet fill valve – PerforMAX and our newest toilet flapper that replaces either a 2″ or 3″ flapper – the Super Flapper

The PerforMAX fill valve sets the standard for performance and is quick and easy to install. It is the most powerful fill valve on the market with 2X greater bowl refill for a more powerful flush.

In October 2025, Buyers Guide in an independent study, named the 400H PerforMAX fill valve as the most popular toilet fill valve: Best Toilet Fill Valves

Toilet flush systems have different size flappers, the Super Flapper is the go-to choice, taking the guessing out of knowing what size flapper you need. This Super Flapper can be converted to a 2” flapper or a 3” flapper. It is quick to convert and easy to install.

Both the flapper and the fill valve have water adjustment features with easy to turn dials that allow you to control and customize the water usage in your toilet. You can use the dials for a more powerful flush or water savings.

This universal design of this 2-piece kit is built to adjust and work with most toilet brands with flapper flush systems.

Turn your super annoying toilet problem into a super easy fix.

• Universal fit for most toilet models and brands
• Easy to Install
• Replaces Small 2” Flappers
• Replaces Large 3” Flappers
• Fixes Running & Noisy Toilets
• Fits Both 2” and 3” Flush Valves
• 2X greater bowl refill for a more powerful flush than standard designs
• Quiet and powerful toilet fill valve
• Customize your water use for both fill valve and flapper for best flush performance or water savings
• 7 year warranty