This HNBR O-Ring has a diameter of 21.9 x 3.5 mm and is Green in color. The hardness of this O-ring 21.9x3.5 - HNBR - 90 Shore A - Red- ORS188104 is 90 Shore A. Alternative names for the compound are Hydrogenated Nitrile Butadiene Rubber, and it is commonly produced by Viton® - Du Pont - 3M - Solvay - Daikin. The O-Ring is typically used in and has an operating temperature range from -25 ºC to 150 ºC. O-Rings 1263270 are referred to as 188104 and have a DIN 3771 size of 21.9 x 3.5. This item is equivalent to and has an None approval. The chemical name of this O-Ring is Hydrogenated nitrile rubber.