S-91128A130 0.812" ID Square Washers

Key Features & Benefits at a Glance

• Superior load distribution with 2" square design for maximum surface contact and stability
• Enhanced corrosion resistance from black-oxide steel surface treatment for extended service life
• Exceptional durability with Rockwell 15N80 hardness rating for heavy-duty applications
• Precise compatibility with 0.812" inner diameter designed specifically for 3/4" screw sizes
• Optimal thickness control between 0.235-0.265" for consistent performance under pressure
• Regulatory compliance assurance meeting RoHS 3 and REACH standards for industrial safety
• Reliable material integrity from steel construction ensuring structural strength in demanding environments

Professional Applications & Engineering Value

These black-oxide steel square washers provide critical engineering solutions where standard round washers fall short. The 2" square configuration significantly increases bearing surface area, preventing fastener pull-through and material deformation in structural steel connections, heavy machinery assembly, and construction applications. The black-oxide coating offers superior corrosion protection without dimensional changes, maintaining precise fit with 3/4" screws while the controlled 0.235-0.265" thickness ensures uniform clamping force distribution. Engineered for industrial environments, these heavy-duty washers withstand extreme vibration and loading conditions while the Rockwell 15N80 hardness guarantees long-term performance without deformation or failure.

Specification Summary & Compliance

Manufactured to precise dimensional standards with 0.812" inner diameter for exact fit with 3/4" screw sizes and controlled thickness tolerance of 0.235-0.265". Constructed from black-oxide steel with Rockwell 15N80 hardness specification. Fully compliant with RoHS 3 (2015/863/EU) including exemption 6(a) for lead as alloying element in steel and REACH (EC 1907/2006) regulations current as of January 17, 2023 covering 233 SVHC substances.