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 19 in Nominal Width 3/16 in Actual Inside Dia 18.955 in Actual Width 0.21 in Dash Number 388 Color Black Durometer 75 Shore A Meets/Exceeds ASTM D2000 SAE J200 Nominal Outside Dia 19 3/8 in Actual Outside Dia 19.375 in Temp Range -15 Degrees to 400 Degrees F FDA Approved No