This Silicone - VMQ - MVQ O-Ring has a diameter of 28x5 mm and is Red in color. The hardness of this O-ring 28x5 - Silicone - VMQ - MVQ - FDA - EC1935/2004 - 70 Shore A - Red - ORS9503 is 70. Alternative names for the compound are Silicone Rubber - PVMQ, and it is commonly produced by Silastic® | Elastosil® | Silopren® | NuSil® | Shin-Etsu Silicone® | Silbione® | Keisper®. The O-Ring is typically used in and has an operating temperature range from -50 ºC to 225 ºC. O-Rings 31828 are referred to as 9503 and have a DIN 3771 size of 28x5. This item is equivalent to and has an FDA - EC1935/2004 approval. The chemical name of this O-Ring is Methyl Vinyl Siliconenrubber / Vinyl Methyl Siloxaan.