S-91114A005 0.115" ID x 0.26" OD ASME B18.21.1 External-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance with external tooth design that bites into mating surfaces to prevent loosening under dynamic loads
• Enhanced corrosion protection through zinc-plated steel construction for extended service life in demanding environments
• Consistent performance with Rockwell C40 hardness ensuring reliable spring action and tooth engagement
• Precision dimensional control with 0.115" ID and 0.26" OD for perfect fit with No. 4 screws
• Industry-standard compliance meeting ASME B18.21.1 specifications for quality assurance
• Environmental responsibility with RoHS 3 and REACH compliance for safe usage in regulated applications
• Optimized thickness range (0.012-0.018") providing ideal compression and spring force for secure locking

Professional Applications & Engineering Value

This external tooth lock washer delivers critical vibration resistance in mechanical assemblies where dynamic forces threaten fastener integrity. The zinc-plated steel construction provides essential corrosion protection while maintaining the Rockwell C40 hardness required for consistent spring performance. The external tooth configuration creates multiple biting points that dig into both the fastener head and mating surface, effectively preventing rotation and loosening in high-vibration environments. Engineered specifically for No. 4 screw applications with precise internal and external diameters, this ASME B18.21.1 compliant washer solves common industrial challenges in automotive, machinery, and electrical equipment where reliable locking under continuous stress is paramount. The combination of material strength and tooth design ensures long-term fastener security without compromising assembly integrity.

Specification Summary & Compliance

Manufactured to ASME B18.21.1 standards with dimensional precision including 0.115" internal diameter, 0.26" external diameter, and thickness ranging 0.012-0.018". The external tooth lock washer features Rockwell C40 hardness for optimal spring performance and meets critical regulatory requirements including RoHS 3 (2015/863/EU) compliance and REACH (EC 1907/2006) compliance with current SVHC monitoring. Designed for use with No. 4 screws in inch system applications, ensuring reliable performance in industrial fastening systems.