SME B18.22.1 Plain Washer Type A SAE   Bolt Size, In. 4 6 8 3/16 12 1/4 5/16 3/8 7/16 1/2 9/16 5/8 3/4 7/8 1 Outside Dia., In. 0.313 0.375 0.438 0.500 0.562 0.625 0.688 0.812 0.922 1.062 1.156 1.312 1.469 1.750 2.000 Inside Dia., In. 0.125 0.156 0.188 0.219 0.250 0.281 0.344 0.406 0.469 0.531 0.594 0.656 0.812 0.938 1.062 Thickness min 0.032 0.049 0.049 0.049 0.065 0.065 0.065 0.065 0.065 0.095 0.095 0.095 0.134 0.134 0.134   　Bolt Size, In. 1 1/8 1 1/4 1 3/8 1 1/2 　Outside Dia., In. 2.250 2.500 2.750 3.000 　Inside Dia., In. 1.250 1.375 1.500 1.625 　Thickness min 0.134 0.165 0.165 0.165