O-Ring No Metal Detectable No X-Ray Detectable System of Measurement Metric Cross Section Shape Round O-Ring Material Viton Durometer (Hardness) Rating Medium Hard Nominal Inside Dia 15.3 mm Nominal Width 2.4 mm Actual Inside Dia 15.3 mm Actual Width 2.4 mm Color Black Durometer 75 Shore A Meets/Exceeds FKM 75 Nominal Outside Dia 20.1 mm Actual Outside Dia 20.1 mm FDA Approved No Package Quantity 25