O-Ring No Metal Detectable No X-Ray Detectable System of Measurement Inch Cross Section Shape Round O-Ring Material Buna N Durometer (Hardness) Rating Medium Hard Nominal Inside Dia 2 5/8 in Nominal Width 1/4 in Actual Inside Dia 2.6 in Actual Width 0.275 in Dash Number 410 Color Black Durometer 70 Shore A Nominal Outside Dia 3 1/8 in Actual Outside Dia 3.15 in Temp Range -40 Degrees to 250 Degrees F FDA Approved No Properties Resistant to Oils Resistant to Water