S-91133A175 0.938" ID Square Washers

Key Features & Benefits at a Glance

• Superior load distribution with a large 4" square surface area to prevent surface damage and material sinking under heavy loads
• Enhanced corrosion resistance thanks to the galvanized steel construction, extending service life in harsh industrial environments
• Exceptional durability provided by Rockwell B40 hardness, ensuring the washer maintains its shape and function under high stress
• Precise fit for 7/8" screws with a 0.938" inner diameter, ensuring secure fastening and reducing installation errors
• Robust thickness tolerance (0.235-0.265") for consistent performance and reliable spacing in demanding applications
• Full regulatory compliance with RoHS 3 and REACH standards, making it suitable for regulated industrial and construction projects
• Heavy-duty construction readiness with inch system specifications ideal for North American industrial standards and replacement parts

Professional Applications & Engineering Value

This heavy-duty square washer is engineered to solve critical challenges in construction and industrial assembly where load distribution and corrosion resistance are paramount. The galvanized steel material, combined with a substantial 4" width and controlled thickness, prevents bolt heads and nuts from embedding into soft materials or deforming under extreme pressure. It is particularly valuable in structural steel connections, timber framing, and machinery bases where 7/8" screws are used, as it increases the clamping area, reduces point loading, and mitigates loosening from vibration. The Rockwell B40 hardness ensures it does not deform, maintaining clamp load integrity over time, while the zinc coating provides a sacrificial layer against moisture and chemicals, making it a reliable choice for outdoor, marine, or chemical-exposed settings without frequent maintenance.

Specification Summary & Compliance

This square washer conforms to inch system dimensions with an ID of 0.938" for 7/8" screw size, a width of 4", and a thickness range of 0.235-0.265". Manufactured from galvanized steel with a hardness of Rockwell B40, it is designed for heavy-duty industrial use. The product is RoHS 3 (2015/863/EU) compliant under exemption 6(a) for lead in steel and is REACH (EC 1907/2006) compliant as of January 17, 2023, meeting environmental and safety standards for professional applications.