Thick Washer, Flat Washer Type Standard, Material Brass, Material Grade/Class Grade 2, Finish Plain, For Screw Size #10, Inside Diameter 0.203 in, Outside Diameter 1/2 in, Maximum Thickness 0.093 in, System of Measurement Inch, Minimum Thickness 0.093 in, Inside Diameter Tolerance +/-0.010 in, Material Quality Standards ASTM B16, Outside Diameter Tolerance +/-0.010 in, Pack Size Small Pack, Resistance Properties , Friction , Rust , Rockwell Hardness B50