S-91128A120 0.562" ID Square Washers

Key Features & Benefits at a Glance

• Enhanced Load Distribution - The 2" square design provides superior surface area contact, preventing surface damage and maintaining structural integrity under heavy loads.
• Superior Corrosion Resistance - Black-Oxide Steel surface treatment offers excellent protection against rust and environmental degradation in demanding industrial settings.
• Precision Fit for 1/2" Fasteners - 0.562" inner diameter ensures perfect compatibility with 1/2" screws, eliminating installation issues and ensuring secure fastening.
• Exceptional Hardness & Durability - Rockwell 15N80 hardness rating guarantees long-term performance under vibration and high-stress conditions without deformation.
• Consistent Thickness Control - 0.235-0.265" thickness range maintains uniform pressure distribution and prevents loosening in critical assemblies.
• Full Regulatory Compliance - Meets RoHS 3 and REACH environmental standards, ensuring safe use in global industrial applications.
• Heavy-Duty Construction - Specifically engineered for high-stress mechanical and construction applications where standard washers fail.

Professional Applications & Engineering Value

This heavy-duty square washer addresses critical engineering challenges in industrial fastening systems where standard round washers prove insufficient. The black-oxide steel construction combined with the square configuration provides maximum bearing surface, effectively distributing clamp load across a wider area to prevent material embedding and surface damage in soft substrates. The precise 0.562" ID ensures perfect alignment with 1/2" screws, eliminating play and maintaining joint integrity under vibration. With Rockwell 15N80 hardness, these washers withstand extreme pressure without deforming, making them ideal for construction equipment, heavy machinery, structural steel connections, and industrial manufacturing applications where reliability is paramount. The corrosion-resistant black-oxide finish extends service life in harsh environments while maintaining dimensional stability.

Specification Summary & Compliance

Manufactured to inch system standards with precise dimensional tolerances, this square washer features 2" width, 0.562" inner diameter, and controlled thickness between 0.235-0.265". The black-oxide steel construction meets industry hardness standards at Rockwell 15N80. Compliant with RoHS 3 (2015/863/EU) under exemption 6(a) for lead as an alloying element in steel and fully compliant with REACH (EC 1907/2006) regulations current as of 01/17/2023, including 233 SVHC substances. Designed specifically for use with 1/2" fasteners in heavy-duty industrial applications.