S-98029A040 1.281" ID x 2.5" OD Oversized Washers

Key Features & Benefits at a Glance

• Enhanced Corrosion Resistance: Black-oxide steel surface treatment provides reliable protection against rust and environmental degradation, extending service life in harsh industrial settings.
• Superior Load Distribution: Large 2.5" outer diameter effectively spreads clamping force, preventing surface damage and maintaining joint integrity under high stress.
• Precision Fit for 1 1/4" Fasteners: Accurate 1.281" inner diameter ensures secure seating and proper alignment with standard screw sizes, reducing installation errors.
• Consistent Mechanical Performance: Rockwell 15N85 hardness rating guarantees dimensional stability and resistance to deformation under sustained pressure.
• Regulatory Compliance Assurance: Meets RoHS 3 and REACH environmental standards, making it suitable for regulated industries and global supply chains.
• Robust Construction: 0.271-0.291" thickness range provides optimal strength-to-weight ratio for demanding mechanical applications.
• Industry-Standard Compatibility: Manufactured to inch system specifications for seamless integration with existing North American equipment and fastening systems.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, this black-oxide steel flat washer addresses critical challenges in machinery assembly, structural steel connections, and equipment manufacturing. The corrosion-resistant black-oxide finish significantly outperforms untreated steel in humid or chemically aggressive environments, reducing maintenance frequency and replacement costs. With its precise 1.281" ID specifically designed for 1 1/4" screw size compatibility, it eliminates play and misalignment issues that compromise joint security. The 2.5" OD provides exceptional bearing surface area, preventing embedment in soft materials and distributing loads effectively across connected components. These features make it particularly valuable for construction equipment, agricultural machinery, and industrial processing systems where vibration resistance and long-term reliability are paramount.

Specification Summary & Compliance

This flat washer maintains standard inch system dimensions with 1.281" inner diameter, 2.5" outer diameter, and 0.271-0.291" thickness range for consistent performance. Manufactured from steel with Rockwell 15N85 hardness rating, it provides reliable mechanical properties for industrial fastening requirements. The product is fully RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant (including 223 SVHC as of 01/17/2022), meeting current environmental regulations for hazardous substance restrictions.