Excellent for all toilets, 1.28, 1.6, 3.5+ gpf (gallons per flush). Fluidmaster® sets the high-performance standard with the 502 PerforMAX® water-saving, adjustable flapper. Fully adjustable for a customized flush. Simply turn the dial left for more water per flush or right for less depending on your needs. Quickly save water and improve flush performance. Built to last, the 502 is our longest lasting flapper. 502 flapper has a 5 years warranty and built-in Microban® technology. 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 for a long lifespan. The Fluidmaster® 502 flapper quickly replaces and upgrades old or corroded 2 in toilet flappers with a high-performance and durable replacement.