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. 4 in, Nominal Width 1/8 in, Actual Inside Dia. 3.984 in, Actual Width 0.139 in, Dash Number 242, Color Black, Durometer 90 Shore A, Meets/Exceeds ASTM D2000, NBR 90, Nominal Outside Dia. 4 1/4 in, Actual Outside Dia. 4.262 in, No, Package Quantity 5