This Silicone - VMQ - MVQ O-Ring is 1.78x1.78mm and in the color Red. The Hardness of this O-ring 1.78x1.78 - VMQ - MVQ - Silicone - FDA - EC1935/2004 - USP Class VI - 3A Sanitary - 70 Shore A - Red - ORS223568 is 70 Shore A.The alternative names of the compound are Silicone Rubber - PVMQ and they are mostly produced by Eriks - Wacker - Eastern Seals - and BlueStar. The O-ring is commonly used in and has an operating temperature range from -55 ºC to 200 ºC. O-rings 6591691 are indicated as 223568 and have a DIN 3771 Size of 1.78x1.78. This item is equal to and has an FDA - EC1935/2004 - USP Class VI - 3A Sanitary Approval. The chemical name of this Oring is Vilnyl Methyl Silicone.