What fits my Fluidmaster 2 or 3 inch unsure?

Manufacturer-backed replacements for the Fluidmaster 2 or 3 inch unsure include Fluidmaster 523A Super Flapper (universal flapper). Fit was checked against the manufacturer sources linked below.

Not sure whether the toilet uses a 2- or 3-inch flapper · Identify by: What you see in the tank

Shopping disclosure: Match My Model may earn a commission from Amazon links, at no added cost to you.

Universal flapper

Fluidmaster 523A Super Flapper

Fluidmaster says this universal flapper replaces both 2-inch and 3-inch flappers for most toilets.

Search Amazon Fluidmaster 523A

✓ Fit checked with manufacturer source

Fit checked Aug 11, 2026Manufacturer sources only for fit verification.

Fluidmaster sizing guidance

Useful when the exact flapper size is the annoying part.

← Check something else