Backup Ring Contoured Material Buna N For Use with AS568A Dash No 031 Thickness 0.049 in Radius 0.087 in Axial Thickness 0.045 in Actual Width 0.053 in Actual Inside Dia 1.768 in Cross Section Shape Rectangular Durometer 90 Shore A Durometer (Hardness) Rating Hard Color Black Temp Range -40 Degrees to 250 Degrees F Package Quantity 100