S-98029A043 0.188" ID x 0.438" OD Oversized Washers

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide steel finish, extending service life in harsh industrial environments.
• Precise dimensional fit with 0.188" ID and 0.438" OD, ensuring secure seating for No. 8 screws and reducing assembly errors.
• Enhanced load distribution from consistent 0.068-0.088" thickness, minimizing surface damage and loosening under vibration.
• Exceptional surface hardness rated at Rockwell 15N85, resisting wear and deformation in high-stress applications.
• Full regulatory compliance with RoHS 3 and REACH standards, guaranteeing safe use in global markets and sensitive industries.
• Reliable performance in inch-system assemblies, offering seamless compatibility with standard No. 8 screw fastenings.

Professional Applications & Engineering Value

Engineered for demanding industrial applications, this black-oxide steel flat washer addresses common issues like galvanic corrosion and fastener failure. The black-oxide coating provides a protective barrier against moisture and chemicals, ideal for outdoor machinery or automotive assemblies. With precise 0.188" ID and 0.438" OD dimensions, it ensures uniform pressure distribution for No. 8 screws, preventing joint fatigue in vibrating equipment. The Rockwell 15N85 hardness enhances durability, making it suitable for heavy-duty use in construction, manufacturing, and electronics—where precision washers are critical for long-term reliability and reduced maintenance costs.

Specification Summary & Compliance

This flat washer adheres to inch-system standards with an internal diameter of 0.188", outer diameter of 0.438", and thickness range of 0.068-0.088" for compatibility with No. 8 screw sizes. Manufactured from black-oxide steel, it meets hardness specifications of Rockwell 15N85 and complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material integrity for industrial and commercial use.