This NBR - Nitrile O-Ring has a diameter of 473.6x5.7 mm and is Black in color. The hardness of this O-ring 473.6x5.7 - NBR - Nitrile - 90 Shore A - Black - ORS203402 is 90 Shore A. Alternative names for the compound are Nitrile Rubber - NBR, and it is commonly produced by Lanxess - Zeon - and LG Chem. The O-Ring is typically used in and has an operating temperature range from -30 ºC to 135 ºC. O-Rings 237981 are referred to as 203402 and have a DIN 3771 size of 473.6x5.7. This item is equivalent to and has an None approval. The chemical name of this O-Ring is Acrylonitrile butadiene rubber.