S-98438A225 0.168" ID x 0.381" OD ASME B18.21.1 External-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance through external tooth design that bites into mating surfaces, preventing screw loosening in high-stress applications
• Exceptional corrosion resistance with 400 Series Stainless Steel construction, ideal for harsh industrial environments and outdoor applications
• Optimized mechanical performance with Rockwell C34 hardness, providing durable locking action without compromising material integrity
• Precision dimensional compatibility with No. 8 screws (0.168" ID, 0.381" OD) ensuring perfect fit and reliable fastening performance
• Industry-standard compliance meeting ASME B18.21.1 specifications for consistent quality and interchangeability
• Environmental regulation compliance with RoHS 3 and REACH standards, suitable for global supply chains and sensitive applications
• Enhanced load distribution through controlled thickness (0.018-0.023") that maintains consistent pressure across fastened surfaces

Professional Applications & Engineering Value

This external tooth lock washer delivers critical vibration-resistant performance for demanding industrial applications where fastener security is paramount. The 400 Series Stainless Steel construction provides excellent corrosion resistance while maintaining the mechanical properties needed for repeated disassembly and reassembly cycles. Engineered specifically for No. 8 screw sizes, these washers solve common vibration-induced loosening problems in machinery, automotive assemblies, and electrical enclosures. The external tooth configuration creates multiple biting points that dig into both the fastener head and base material, creating a mechanical lock that outperforms standard flat washers. This design is particularly valuable in applications subject to thermal cycling, mechanical shock, or constant vibration where maintaining clamp load is essential for system integrity and safety.

Specification Summary & Compliance

This precision external tooth lock washer features dimensional specifications of 0.168" internal diameter and 0.381" outer diameter with thickness maintained between 0.018-0.023". Manufactured to ASME B18.21.1 standards for inch-system tooth lock washers, ensuring dimensional accuracy and performance reliability. The component is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, making it suitable for international industrial applications and environmentally conscious manufacturing processes. The Rockwell C34 hardness specification guarantees consistent mechanical performance across production batches.