O-Ring No Metal Detectable No X-Ray Detectable System of Measurement Inch Cross Section Shape Round O-Ring Material Viton Durometer (Hardness) Rating Medium Hard Nominal Inside Dia 18 in Nominal Width 1/4 in Actual Inside Dia 17.955 in Actual Width 0.275 in Dash Number 465 Color Black Durometer 75 Shore A Meets/Exceeds ASTM D2000 SAE J200 Nominal Outside Dia 18 1/2 in Actual Outside Dia 18.505 in Temp Range -15 Degrees to 400 Degrees F FDA Approved No