Backup Ring Contoured Material Buna N For Use with AS568A Dash No 359 Thickness 0.076 in Radius 0.262 in Axial Thickness 0.06 in Actual Width 0.183 in Actual Inside Dia 5.778 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 10