The Fluidmaster 503 Universal Toilet Flapper is designed to be a quick and effective replacement toilet flapper. With a flexible design, this flapper can be used on flush valves with or without mounting ears and fits most 2 brass or plastic flush valves. Quickly replace old problem flappers with this universal design. The included kink-free metal chain eliminates flapper hang up, while the built-in microban extends flapper usage. 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 Fluidmaster 503 2 flapper, a flexible design for your toilet.One-piece replacement flapper with a universal fit,Universal design fits most toilets, including American Standard actuator units.,Attaches to existing mounting ears on overflow pipe,Built-in adapter ring fits most overflow pipes without mounting ears,Strong, kink-free metal chain