• Chlorine and hard water-resistant Solid frame for the best seal every time, no twisting Built-in Microban fights breakdown due to bacteria Easy to install, works on most toilets

Stop a running toilet with the Fluidmaster® 501 universal chlorine-resistant toilet flapper. The 501 flapper is built-to last in any water condition with its chlorine-resistant properties. Unlike flexible flappers, the 501 flapper features a solid frame that doesn't twist for the best seal every time - so you never have worry about jiggling the toilet handle again. The 500 universal Flapper is best suited for use with 3.5+ gpf toilets. Only Fluidmaster® has toilet flappers with built-in Microban® protection. Not just simply a coating, Microban® is specially built-into the construction of our flappers to fight flapper breakdown and combat bacteria.