Flat Washer, Flat Washer Type Standard, Dimensional Standards ASME B 18.22. 1, Material Stainless Steel, Material Grade/Class 316, Finish NL-19, For Screw Size 1/2 in, Inside Diameter 0.531 in, Outside Diameter 1 1/16 in, Maximum Thickness 0.098 in, System of Measurement Inch, Minimum Thickness 0.098 in, Color Silver, Material Quality Standards Not Applicable, Pack Size Small Pack, Resistance Properties Corrosion-Resistant, Rockwell Hardness B80, Thickness Tolerance +/- 0.023 in. This item has been restricted from sale in the following state (s): []