Back Home / Fasteners / Washers / FLAT WASHER USS ZINC 5/8″ FLAT WASHER USS ZINC 5/8″ SKU: FW58 Categories: Fasteners, Washers Used to improve stress distribution, and to span large holes. USS PATTERN. Made from low carbon steel, zinc plated. Outside Diameter: 1-3/4″ Inside Diameter: 11/16″ Case Quantity: 50 Log In For Pricing