Features: OOTDTY fresh and high-quality Material: Nitrile rubber,Features: dependable sealing and getting old resistance. Pressure diaphragm of 45mm/50mm gasoline water heater. A pleasant helper for upkeep of water heaters, gas valves, Mainly used to increase water pressure. When the water movie ruptures, it'll leak. When the water volume is large, the water strain on the water film will decrease, and there's virtually no water leakage. When the amount of water is small, the water stress at the water film will increase, but the leakage fee may be faster. ThePackage Includes: 10 goods of 45mm/50mm size. Specifications: Material: Plastic Weight: 25g/35g Size: 45mm/50mm Color: Black Package Includes: 1x Pressure Diaphragm Note: 1 allow 1-2cm mistakes because of guide measurement, make sure that you don't mind before you order. 2 to the variation between diversified monitors, the image won't mirror the actual color of the item.