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. 3 1/2 in, Nominal Width 1/8 in, Actual Inside Dia. 3.484 in, Actual Width 0.139 in, Dash Number 238, Color Black, Durometer 70 Shore A, Meets/Exceeds ASTM D2000, NBR 70, Nominal Outside Dia. 3 3/4 in, Actual Outside Dia. 3.762 in, FDA Approved No, Package Quantity 25