This FFKM - FFPM O-Ring is 37.2 x 3mm and in the color Black. The Hardness of this O-ring 37.2x3 - FFKM - FFPM - Low Temp - Kalrez 0040 - 75 Shore A - Black - ORS220386 (Equivalent) is 75 Shore A.The alternative names of the compound are FFPM – Dupont Kalrez and they are mostly produced by Chemraz® - Simriz® - Kalrez® - Spectrum - Triazinico - Isolast® - Parofluor® - Fluorez - Perlast® - HPSealing® - Perfluor® - Polymax. The O-ring is commonly used in and has an operating temperature range from -40 ºC to 250 ºC. O-rings 621077 are indicated as 220386 and have a DIN 3771 Size of 37.2 x 3. This item is equal to Dupont Kalrez 0040, Greene Tweed Chemraz 505 and has an LT40 Approval. The chemical name of this Oring is Perfluoroelastomer.