The Korky Plus 2 in adjustable toilet tank flapper features an adjustable float to help control flush volume. Simply slide the adjustable float up for water savings or down for increased flush volume. The exclusive longest lasting red rubber resists chlorine, bacteria, city water treatment, hard water and well water. The adjustable flapper fits most toilets, including Kohler, Glacier Bay and American Standard models. Made of flexible rubber for a tight seal and easy to install.