O-Ring Viton AS568 Dash Number 468 Actual Width 0.275 In. Actual Inside Dia 19.455 In. Outside Dia 20.005 In. Cross Section Shape Round Durometer Rating Medium Hard Durometer 90 Shore A Nominal Width 1/4 In. Nominal Inside Dia 19-1/2 In. Nominal Outside Dia 20 In. Color Black Temp Range -15 Degrees to 400 Degrees F Meets/Exceeds SAE J200 ASTM D2000