Backup O-Ring, Material Buna-N, For Use with AS568A Dash No. 039, Thickness 0.049 in, Radius 0.087 in, Axial Thickness 0.045 in, Actual Width 0.053 in, Actual Inside Dia. 2.768 in, Cross Section Shape Rectangular, Durometer 90A, Durometer (Hardness) Rating Hard, Color Black, Temp. Range -40 Degrees to 250 Degrees F, Package Quantity 50