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 12.1 mm Nominal Width 1.6 mm Actual Inside Dia 12.1 mm Actual Width 1.6 mm Color Black Durometer 75 Shore A Meets/Exceeds FKM 75 Nominal Outside Dia 15.3 mm Actual Outside Dia 15.3 mm FDA Approved No Package Quantity 25