Fluidmaster Replacement Flush Valve Seal, For Use With Mansfield #210 & #211 Toilets, A Quick & Easy Way To Eliminate Leaks On Your Specialty Flush Valve Toilet, Designed To Be A Direct OEM Replacement For A Perfect Fit & Secure Seal, Built To Last, Silicone Seal Lasts Up To 10 Times Longer, Is Chlorine & Hard Water Resistant.