S-91757A101 0.115" ID x 0.27" OD ASME B18.21.1 Internal-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance with internal teeth that bite into mating surfaces to prevent loosening under dynamic loads
• Corrosion-resistant 18-8 stainless steel construction ensures long-term reliability in harsh industrial environments
• Precision-engineered dimensions (0.115" ID, 0.27" OD) provide perfect fit for No. 4 screw applications
• ASME B18.21.1 certification guarantees consistent quality and performance meeting industry standards
• Environmental compliance with RoHS 3 and REACH regulations for safe use in regulated industries
• Optimized thickness range (0.012-0.018") allows for proper compression and spring action in confined spaces
• Internal tooth design concentrates locking force directly under the screw head for maximum securing effectiveness

Professional Applications & Engineering Value

This internal tooth lock washer delivers critical vibration-resistant performance in demanding applications where fastener security is paramount. The 18-8 stainless steel composition provides excellent corrosion resistance for outdoor equipment, marine components, and chemical processing installations. Engineered specifically for No. 4 screw size applications, the internal teeth create multiple biting points that dig into both the fastener and workpiece, maintaining clamp force where standard flat washers fail. This ASME B18.21.1 certified solution prevents costly downtime in assembly lines, electrical enclosures, and precision machinery by eliminating the need for frequent retightening. The inch system measurement ensures compatibility with North American equipment specifications while the RoHS and REACH compliance makes it suitable for electronics, automotive, and aerospace industries with strict material restrictions.

Specification Summary & Compliance

This tooth lock washer features precision dimensions with 0.115" internal diameter and 0.27" outer diameter, manufactured to ASME B18.21.1 standards for consistent performance. The internal tooth configuration provides superior locking action compared to external tooth designs. The washer is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, containing no restricted substances above threshold limits. Manufactured from 18-8 stainless steel, it offers excellent corrosion resistance while maintaining the spring properties necessary for effective vibration resistance in industrial applications.