Lock Washer, Carbon Steel, Carbon Steel, Finish Zinc Plated, Fits Bolt Sizes 3/4 In., 3/4 In., Inside Dia. 19.8 mm, Outside Dia. 30.7 mm, Thickness 5.66 mm, Thickness Tolerance +/- 0.28 mm, Color Gray, Rockwell Hardness C46, Helps Prevent Loosening, For Use With Bolts, Package Quantity 100. This item has been restricted from sale in the following state (s): []