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 1 7/8 in Nominal Width 3/16 in Actual Inside Dia 1.85 in Actual Width 0.21 in Dash Number 328 Color Clear with Black Core Durometer 90 Shore A Meets/Exceeds ASTM D2116 Nominal Outside Dia 2 1/4 in Actual Outside Dia 2.27 in Temp Range -15 Degrees to 400 Degrees F FDA Approved Yes