Features: OOTDTY fresh and effective Material: Nitrile rubber,Features: reliable sealing and growing older resistance. Pressure diaphragm of 45mm/50mm gas water heater. A pleasant helper for maintenance of water heaters, fuel valves, Mainly used to extend water pressure. When the water film ruptures, it is going to leak. When the water quantity is large, the water strain at the water movie will decrease, and there's almost no water leakage. When the quantity of water is small, the water pressure at the water movie will increase, but the leakage fee could 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 thanks to handbook measurement, simply you should definitely don't mind before you order. 2 to the difference between assorted monitors, the picture won't replicate the actual color of the item.