O-Ring, No Metal Detectable, No X-Ray Detectable, System of Measurement Metric, Cross Section Shape Round, O-Ring Material Buna N, Durometer (Hardness) Rating Medium Hard, Nominal Inside Dia. 12 mm, Nominal Width 2.5 mm, Actual Inside Dia. 12 mm, Actual Width 2.5 mm, Color Black, Durometer 70 Shore A, Meets/Exceeds NBR 70, Nominal Outside Dia. 17 mm, Actual Outside Dia. 17 mm, FDA Approved No, Package Quantity 50