Thick Washer Thick Case Hardened Steel Finish Black Oxide Fits Bolt Sizes 3/8 In. Inside Dia 13/32 In. Outside Dia 7/8 In. Thickness 1/8 In. Thickness Tolerance +/-0.010 In. Rockwell Hardness C40 Load Distributing For Use With Die And Jig Fixture Setup Package Quantity 25