Lock Washer, External Tooth, Type A, Carbon Steel, Finish Zinc, Fits Bolt Sizes #8, Inside Dia. 0.176 In., Outside Dia. 0.381 In., Thickness 0.023 In., Rockwell Hardness C40 to C50, Helps Prevent Loosening, For Use With Small Screws, Meets/Exceeds ASME B 18.21. 1, Refills -, Package Quantity 100