Allstar Performance USS pattern flat washer sized for 5/16in fasteners. Made from steel with a zinc oxide finish. Sold as a set of 25.
- Inside Diameter: 0.313 in
- Outside Diameter: 0.902 in
- Thickness: 0.1 in
- Material: Steel
- Finish: Zinc Oxide
- Pack Quantity: 25
Spec Sheet: Allstar Spec Sheet
Compatibility
Compatible with 5/16in USS-pattern bolts and fasteners. USS washers have a larger outside diameter than SAE or AN washers of the same nominal thread size, so do not substitute a USS washer where an SAE or AN spec washer is required.
FAQ
What size fastener does this washer fit?
This washer fits a 5/16in USS-pattern fastener, with an inside diameter of 0.313 in.
What is the outside diameter of this washer?
The outside diameter is 0.902 in, per the USS washer pattern.
What material is this washer made from?
This washer is made from steel with a zinc oxide finish.
How many washers are included?
This listing includes a set of 25 washers.
Is this the same as an SAE washer in this size?
No. USS and SAE washers in 5/16in have different outside diameters. This is a USS-pattern washer; check the SAE-specific listing if an SAE washer is required.

