Flat washers distribute the load of a fastener over a wider surface area, helping protect the material and prevent damage as the fastener is tightened.

Nominal Size: 5/16"
Inside Diameter: 3/8"
Outside Diameter: 7/8"
Thickness: 5/64"
Material: Stainless Steel
Hardness: 18-8
Style: USS
Type: Flat Washer
A flat washer is a thin, usually round, plate with a hole in the middle that is normally used to distribute the load of a threaded fastener. USS flat washers have a large, wider body. SAE flat washers are machined to a tighter specification and have a smaller outside diameter.