S-98438A031 0.384" ID x 0.694" OD ASME B18.21.1 External-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance through external teeth that bite into mating surfaces, preventing fastener loosening in high-stress applications
• Exceptional corrosion resistance with 400 Series Stainless Steel construction, ideal for harsh industrial environments
• Optimized dimensional precision with 0.384" ID and 0.694" OD ensuring perfect fit for 3/8" fasteners
• Enhanced durability from Rockwell C34 hardness, maintaining locking performance under repeated loading cycles
• Industry-standard compliance with ASME B18.21.1 specifications for reliable mechanical performance
• Environmental responsibility through RoHS 3 and REACH compliance, meeting global regulatory requirements
• Consistent thickness control (0.032-0.040") for uniform clamping force distribution across assembly surfaces

Professional Applications & Engineering Value

This external tooth lock washer delivers critical vibration-resistant performance in demanding industrial applications where fastener security is paramount. Engineered from 400 Series Stainless Steel, the washer's external teeth create multiple biting points that dig into both the fastener and workpiece, effectively resisting rotational forces and vibration-induced loosening. The Rockwell C34 hardness ensures the teeth maintain their biting capability through numerous installation cycles without deformation. Particularly valuable in machinery, automotive, and heavy equipment assemblies, this 3/8" screw size washer addresses the common failure point of joint relaxation under dynamic loading conditions. The external tooth configuration provides superior locking action compared to standard flat washers, making it essential for critical connections in vibration-prone environments where maintenance access is limited.

Specification Summary & Compliance

This precision tooth lock washer features dimensional specifications of 0.384" internal diameter, 0.694" outer diameter, and thickness ranging from 0.032" to 0.040". Manufactured to ASME B18.21.1 standards for mechanical properties and performance, the washer ensures consistent quality and reliability. The product maintains full compliance with RoHS 3 (2015/863/EU) restrictions on hazardous substances and REACH (EC 1907/2006) regulations regarding chemical safety. Manufactured in the inch system with precise tooth geometry, this washer delivers reliable locking performance for industrial fastening applications requiring certified quality standards.