40545 USS 1/2" Flat Washers Box/100

Overview The 40545 USS 1/2" Flat Washers (03830) are designed for load distribution in threaded fastener assemblies. Manufactured by Midwest Fastener Corp, these USS-series flat washers are sold in a box of 100 pieces, making them suited for production, maintenance, and construction applications requiring consistent hardware supply. Specification Detail MPN 03830 Brand Midwest Fastener Corp Series USS (Unified Standard Series) Bolt Size 1/2" Quantity per Box 100 pieces Technical Features USS Series body geometry: features a larger outside diameter compared to SAE washers, providing a wider bearing surface to distribute fastener load across a greater area and reduce material pull-through. Flat, thin plate profile: seats flush beneath a threaded fastener head or nut, ensuring even load transfer without adding unnecessary stack height to the assembly. Center hole sized for 1/2" fasteners: provides a direct fit for standard 1/2" bolts and screws, eliminating the need for sizing adjustments on the job site. Box quantity of 100 pieces: supports bulk fastening tasks and reduces per-unit cost for repetitive or high-volume assembly work. USS vs. SAE — Key Distinction USS flat washers feature a larger, wider outer diameter than SAE flat washers. SAE washers are machined to a tighter specification with a smaller outside diameter. USS washers are the preferred choice where a broader load-bearing footprint is required or where the mating surface material is softer and more susceptible to indentation under clamp load. Applications General construction and structural bolted connections requiring load distribution. Wood framing and decking assemblies where fastener pull-through into softer materials is a concern. Mechanical and equipment assembly using 1/2" threaded fasteners. Maintenance and repair operations where a standard USS-specification washer is specified.