This FFKM - FFPM O-Ring has a diameter of 47.37x1.78 mm and is Black in color. The hardness of this O-ring 47.37x1.78 - FFKM - FFPM - F909ZLT - AED - Norsok M710 - Low Temp. (-40°C) - 90 Shore A - Black - ORS66553 is 90. 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 -40 ºC to 250 ºC. O-Rings 541379 are referred to as 66553 and have a DIN 3771 size of 47.37x1.78. This item is equivalent to and has an AED - Norsok M710 - Lage Temp. (-40°C) approval. The chemical name of this O-Ring is Perfluorcarbonrubber / Perfluoroelastomeer.