Sq Washer for 3/4 Bolt .813 ID 4.00 Wd 1, Dimensional Standards AMPG 2017 SQ.01, Material Stainless Steel, Material Grade/Class 18-8, Finish Plain, For Screw Size 3/4 in, Inside Diameter 0.813 in, Outside Diameter Not Applicable, Maximum Thickness 17/64 in, System of Measurement Inch, Minimum Thickness 15/64 in, Made in North America Made in North America, Material Quality Standards ASTM A582