S-98029A041 0.125" ID x 0.312" OD Oversized Washers

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide steel finish, extending service life in demanding environments
• Precise dimensional fit with 0.125" ID and 0.312" OD ensuring optimal alignment and load distribution for No. 4 screws
• Enhanced surface durability from Rockwell 15N85 hardness rating, resisting deformation under pressure
• Consistent thickness control (0.068-0.088") for uniform clamping force and vibration resistance
• Full regulatory compliance with RoHS 3 and REACH standards, ensuring safe use in global markets
• Reliable load distribution across fastener assemblies, preventing surface damage and loosening

Professional Applications & Engineering Value

These black-oxide steel flat washers deliver critical engineering solutions where corrosion resistance and dimensional precision are paramount. The black-oxide surface treatment creates a protective barrier against moisture and chemicals, significantly reducing failure risks in industrial equipment, automotive assemblies, and outdoor machinery. Engineered with exact 0.125" ID specifications for No. 4 screw applications, they prevent fastener loosening through even load distribution while maintaining Rockwell 15N85 hardness to withstand repeated stress cycles. This combination of material properties and manufacturing precision addresses common assembly challenges including galvanic corrosion, surface marring, and vibration-induced joint failure.

Specification Summary & Compliance

Manufactured to standard inch dimensions with 0.125" inner diameter, 0.312" outer diameter, and controlled 0.068-0.088" thickness range. These flat washers meet industry standards for dimensional accuracy and are fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, including the latest SVHC updates. The black-oxide steel construction with Rockwell 15N85 hardness ensures consistent performance across industrial applications.