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 8 1/4 in Nominal Width 3/16 in Actual Inside Dia 8.225 in Actual Width 0.21 in Dash Number 370 Color Black Durometer 90 Shore A Meets/Exceeds ASTM D2000 NBR 90 Nominal Outside Dia 8 5/8 in Actual Outside Dia 8.645 in FDA Approved No Package Quantity 2