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 Very Hard Nominal Inside Dia 2 3/8 in Nominal Width 1/16 in Actual Inside Dia 2.364 in Actual Width 0.07 in Dash Number 036 Color Black Durometer 90 Shore A Meets/Exceeds ASTM D2000 NBR 90 Nominal Outside Dia 2 1/2 in Actual Outside Dia 2.504 in FDA Approved No Package Quantity 10