The Fluidmaster 501P21 Universal Chlorine-Resistant Toilet Flapper is a longer lasting, high quality flapper replacement. Made to fit most 2" flush valve toilets with it's universal design. Built tough with chlorine-resistant materials and built-in Microban. Only Fluidmaster has toilet flappers with built-in Microban protection. Not just simply a coating, Microban is specifically built into the construction of our flappers to fight flapper breakdown and combat bacteria. The solid frame ensures a secure seal, by resisting bending, or twisting during flushing, and the kink-free chain eliminates flapper hang-up and running toilets. Replace an old or faulty flapper fast with Fluidmaster's 501 Solid Frame Universal Flapper. 5 year manufacturer's warranty.