Characteristics for viton o ring good physical and chemical properties. Description of ... ECO, CSM, FKM, FPM, etc.2. Characteristics: good physical and chemical properties.3. Hardness: 70~90A or as ... : exactly upon your request or standard tolerance.5. Color: black, transparent, green, red, yellow, grey, purple, pink, ... time: 1~3 weeks.8. Small order quantity is welcomed. black viton o ring for valve