The major use of washers is to provide a smooth bearing surface. Washers are generally used at the basal part of the head of a nut / bolt. The chemical, mechanical, and dimensional requirements with regards to hardened washers are covered under the ASTM specification F436. These washers are completely hardened / carburized to add strength, but they appear to be physically smaller when compared to the standard F844 flat washers. Except for low carbon steel bolts, these hardened washers are expert recommended washers to suit any other fastener.
Diameters: 1/2″ – 2-3/4″
Finish: Plain and hot-dip galvanized