O-Ring No Metal Detectable No X-Ray Detectable System of Measurement Inch Cross Section Shape Round O-Ring Material EPDM Durometer (Hardness) Rating Medium Hard Nominal Inside Dia 3 5/8 in Nominal Width 3/16 in Actual Inside Dia 3.6 in Actual Width 0.21 in Dash Number 342 Color Black Durometer 70 Shore A Meets/Exceeds ASTM D2000 EPDM 70 Nominal Outside Dia 4 in Actual Outside Dia 4.02 in FDA Approved No Package Quantity 25