Fluidmaster 504BX Replacement Toilet Flapper

Product Description

The FLUIDMASTER 504BX is a replacement toilet flapper designed to restore proper flush valve operation in residential toilets. The flapper seats against the flush valve seat at the base of the tank, creating a watertight seal that holds water until the flush handle is activated. When the seal degrades over time, toilets run continuously or fail to flush fully. Replacing the flapper is a straightforward repair that plumbers and capable DIYers perform without specialized tools. The 504BX ships as a single piece and is a direct drop-in replacement for compatible flush valve assemblies.

This flapper is suited for standard residential toilet tank applications. It is installed during routine maintenance calls when a running toilet is traced to a worn or warped flapper seal. The single-unit pack is appropriate for individual repairs. Plumbing contractors often stock this part for service calls involving common tank-type toilets in residential and light commercial settings.

Key Features

• Direct replacement flapper for compatible toilet flush valves
• Restores watertight seal to stop running toilet conditions
• Single-piece unit ready for immediate installation
• No special tools required for installation

Compatibility

Designed as an OEM-style replacement for compatible residential toilet flush valve assemblies. Refer to the existing flush valve markings or the toilet manufacturer documentation to confirm fitment before installation.

Installation Notes

Installation is performed by a licensed plumber or a qualified DIYer familiar with toilet tank components. Shut off the supply valve at the wall before beginning work and flush the tank to drain it. Unhook the old flapper from the overflow tube ears and disconnect the chain from the flush lever before installing the new unit. Follow all applicable IPC guidelines for potable water system repairs.