Fender Washer Standard 316 Stainless Steel Finish Plain Fits Bolt Sizes 5/16 In Inside Dia 21/64 In Outside Dia 5/8 In Thickness 0.063 In Thickness Tolerance +/-0.007 Rockwell Hardness B80 For Use With Screws and Studs Package Weight 0.18 Lbs Package Quantity 10