5/16" SAE Flat Washers, 3/8" Inside Dia, 7/8" Outside Dia, 5/64" Thickness, Steel, Zinc Plated - 5lb.

Flat Washers are a thin, flat, circular steel part with a centrally located hole. Washers are designed for assembly around a bolt or screw, between the bearing surface of the fastener and the part to which it is attached. Flat washers are used to improve stress distribution and to span large clearance holes. SAE flat washers are similar to USS washers, but with a slightly smaller inside and outside diameters. Also, most BUT NOT ALL SAE washers are made from thinner materials than USS washers. SAE washers were designed to serve similar purposes as USS washers, but specifically to meet the requirements in the field of automotive engineering.