Reliable sealing and anti-aging. Good helper for water heater, fuel valve and other maintenance. Made of positive materials, it can be used for a long time. Replacing the previous one is a good choice. Type: Gas water heater kit Colour: black Material: rubber Size: 54mm diameter Package Contents: a hundred x strain diaphragm Only the above equipment content, different merchandise aren't included. Note: Light taking pictures and various reveals may cause the color of the thing within the picture barely diverse from the genuine thing. The length allowed error is +/- 1-3cm.