Compatible with 3-inch Gerber 99-788: High efficiency and long life lasting toilet flapper replacement kit for 3 inch toilet flush valves. It is compatible with Gerber toilet flapper 99-788. NOTE: It is not universal and incompatible with Kohler toilets and Mansfield toilets. Please measure the size of your old toilet flapper or the toilet flush valve before purchasing Water Conserve Flushing: Features a superior sealing interface for compatibility with 3 inch flush valve, augmenting the efficiency of the flushing system and diminishing water wastage and leakage Reliable Rubber: iFealClear toilet stopper flapper is made of chlorine-resistant rubber for superior durability and corrosion resistance, which keeps the function stable even under hard water conditions. Equipped with anti-corrosive stainless steel chain for preventing breakage or jamming Easy to Install: No tools need for installation, package include stainless steel chains with clip hooks. Use this toilet flapper assembly comtatible with gerber toilet parts to replace the old leaky one. Solve the running toilet tank easily. Please make sure that there is no dust or dirt accumulated on the toilet flapper and the toilet flush valve to prevent water leakage Note: Kindly make sure to measure the opening in your toilet tank or your old toilet flapper is 3". The length of the chain is 10”. The holes of the two toilet flapper attachment arms are of the same size. The length between attachment arms is 2.83 inches and the width of attachment arm is 1 inch Optimally Fitted-toilet bowl flapper replacement compatible with Gerber 99-788. Great Quality- Specialized blue flexible rubber for good sealing. Easy To Install- No tools and plumber needed, Includes stainless steel chain clip hook. Good Sealing- A standard 3-inch toilet flapper, which can QUICKLY FIX running and leaking toilets.