O-Ring No Metal Detectable No X-Ray Detectable System of Measurement Inch Cross Section Shape Round O-Ring Material HNBR Durometer (Hardness) Rating Medium Hard Nominal Inside Dia 2 1/4 in Nominal Width 1/8 in Actual Inside Dia 2.2 in Actual Width 0.139 in Dash Number 228 Color Black Durometer 80 Shore A Nominal Outside Dia 2 1/2 in Actual Outside Dia 2.512 in Temp Range -55 to 300 Degrees F FDA Approved No