S-90339A031 Easy-Install Slotted Washers

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide steel finish for extended service life in demanding environments
• Precision slot alignment (9/32" width, 1/2" depth) ensures secure fit and prevents rotation during assembly
• Exceptional surface hardness (Rockwell 15N80) maintains dimensional stability under high-load conditions
• Versatile compatibility designed for No. 10, No. 12, No. 14, and 1/4" screws across multiple applications
• Consistent thickness control (0.240-0.260") provides uniform load distribution and vibration resistance
• Regulatory compliance assurance with RoHS 3 and REACH standards for global industrial use
• Optimized 0.75" OD design offers maximum bearing surface while maintaining compact installation footprint

Professional Applications & Engineering Value

These black-oxide steel slotted washers deliver critical performance in industrial fastening systems where vibration resistance and corrosion protection are paramount. The precision-engineered slot configuration prevents rotational slippage in high-torque applications, while the Rockwell 15N80 hardness rating ensures the washer maintains its structural integrity under repeated loading cycles. Ideal for heavy machinery assembly, electrical enclosures, and automotive components, these inch-system washers provide reliable interface protection between fastener heads and mating surfaces. The controlled thickness variation guarantees consistent clamping force distribution, eliminating point loading that can lead to material deformation or joint failure in critical connections.

Specification Summary & Compliance

Manufactured to precise dimensional standards with 0.75" outer diameter and controlled thickness range of 0.240-0.260". Features standardized slot dimensions of 9/32" width and 1/2" depth for compatibility with No. 10 through 1/4" screw sizes. Material certification includes Rockwell 15N80 hardness verification and full compliance with RoHS 3 (2015/863/EU) under exemption 6(a) for lead as steel alloying element, along with REACH (EC 1907/2006) compliance current through January 17, 2023 SVHC listing.