This FFKM - FFPM - Kalrez O-Ring is mm and in the color White. The Hardness of this O-ring 25x3.55 - FFKM - FFPM - FDA - EC1935/2004 - USP Class VI - Kalrez 6880 & Kalrez 6221 - 70 Shore A - White - ORS555409 (Equivalent) is 70 Shore A.The alternative names of the compound are FFPM – Dupont Kalrez and they are mostly produced by Kalrez® - Simriz® - Chemraz® - Spectrum® - Triazinico® - Isolast® - Parofluor® - Fluorez® - Perlast® - Perfluor®. The O-ring is commonly used in and has an operating temperature range from -20 ºC to 270 ºC. O-rings 555409 are indicated as 216510 and have a DIN 3771 Size of . This item is equal to and has an FDA - EC1935/2004 - USP Class VI Approval. The chemical name of this Oring is Perfluoroelastomer.