Lock Washer, 316 Stainless Steel, Plain Finish, Fits Bolt Sizes 5/16", Inside Dia. 0.340", Outside Dia. 0.530", Thickness 0.080", Thickness Tolerance +/- 0.01", Rockwell Hardness Min. 52 HRC Case Hardened, Meets/Exceeds DIN 25201, Package Quantity 200 .
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