O-Ring No Metal Detectable No X-Ray Detectable System of Measurement Inch Cross Section Shape Round O-Ring Material Buna N Durometer (Hardness) Rating Medium Hard Nominal Inside Dia 4 1/4 in Nominal Width 3/32 in Actual Inside Dia 4.237 in Actual Width 0.103 in Dash Number 156 Color Black Durometer 70 Shore A Meets/Exceeds ASTM D2000 NBR 70 Nominal Outside Dia 4 7/16 in Actual Outside Dia 4.443 in FDA Approved No Package Quantity 10