The Genuine TOTO 3 in flapper by Korky is fully adjustable to fit all 3 in TOTO toilet models|It is made with the longest lasting material on the market|The adjustable flapper has 8 settings to ensure it fits all TOTO models|Replaces the following TOTO® flappers: THU138S, THU175S, THU331S, THU140S, THU299S, THU253S, THU277S, THU347S, THU275S, THU332S, and THU369S|Made of flexible rubber for a tight seal and easy to install|Fits 3 in flush valve opening