Form: This specification covers a butadiene-acrylonitrile (NBR) rubber in the form of molded rings. Application: Sealing rings for use at temperatures as low as -55??(-65?? w ere resistance to fuel is required. The cross-section of such rings is usually not over 0.275 in. (7.0 mm} in diameter or thickness. Standard sizes are as shown in AS 568.
SAE AMS7270H-1987 history
2022SAE AMS7270M-2022 Rubber: Acrylonitrile-Butadiene (NBR) Fuel Resistant 65 to 75 Type A Hardness for Seals in Fuel