A good helper for maintenance of water heaters, valves, Pressure diaphragm of 45mm/50mm water heater. The package includes: 10 pieces of 45mm/50mm size. Mainly used to increase water pressure. When the water film ruptures, it will leak. When the water volume is large, the water pressure on the water film will decrease, and there is almost no water leakage. When the amount of water is small, the water pressure on the water film will increase, but the leakage rate will be faster. Nitrile rubber, features: sealing and aging resistance.