The Fluidmaster 5403P4 3' Water-Saving Adjustable Flapper is specifically made to fit newer 3' flush valve toilets. Quick and easy to install, and featuring a universal design to fit most toilets with 3' flush valves. The adjustable flapper arms help to fit more models. While the adjustable dial offers a customizable water use per flush. You simply turn to adjust for more or less depending on your needs. This long lasting flapper also features a durable silicone seal that lasts up to 10x longer than standard designs. For use in 1.28 & 1.6 GPF HET toilets with 3' flush valves. Eliminate leaks and save water with this long lasting solution, the Fluidmaster 5403 Universal Adjustable 3' Toilet Flapper.