This FFKM - FFPM O-Ring has a diameter of 31 x 3.5 mm and is Black in color. The hardness of this O-ring 31x3.5 - FFKM - FFPM - F758Z94 - General Purpose (+270°C) - FDA - 75 Shore A - Black - ORS176509 is 75. Alternative names for the compound are FFKM - FFPM, and it is commonly produced by Kalrez® | Simriz® | Chemraz® | Perlast® | Isolast® | Parofluor®. The O-Ring is typically used in and has an operating temperature range from -20 ºC to 275 ºC. O-Rings 531718 are referred to as 176509 and have a DIN 3771 size of 31 x 3.5. This item is equivalent to and has an Algemene Doeleinden (+270°C) - FDA approval. The chemical name of this O-Ring is Perfluorcarbonrubber / Perfluoroelastomeer.