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 Actual Inside Dia 0.414 in Actual Width 0.072 in Dash Number 905 Color Black Durometer 70 Shore A Meets/Exceeds ASTM D2000 SAE J200 Nominal Outside Dia 5/16 in Actual Outside Dia 0.558 in Temp Range -40 Degrees to 250 Degrees F FDA Approved No Package Quantity 25