O-Ring No Metal Detectable No X-Ray Detectable System of Measurement Inch Cross Section Shape Round O-Ring Material FEP with Viton Core Durometer (Hardness) Rating Very Hard Nominal Inside Dia 8 in Nominal Width 1/4 in Actual Inside Dia 7.975 in Actual Width 0.275 in Dash Number 445 Color Clear with Black Core Durometer 90 Shore A Meets/Exceeds ASTM D2116 Nominal Outside Dia 8 1/2 in Actual Outside Dia 8.525 in Temp Range -15 Degrees to 400 Degrees F FDA Approved Yes