S-90412A120 4.3 mm ID x 8 mm OD DIN 6797 External-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance with external teeth that bite into mating surfaces to prevent fastener loosening under dynamic loads
• Exceptional corrosion resistance thanks to 316 stainless steel construction, ideal for harsh environments and chemical exposure
• Precision dimensional control with 4.3mm ID and 8mm OD ensuring perfect fit for M4 fastener applications
• Reliable performance standardization through DIN 6797 compliance, guaranteeing consistent quality and interchangeability
• Enhanced safety compliance with RoHS 3 and REACH regulations for environmentally responsible industrial use
• Optimized load distribution from 0.4-0.6mm thickness providing stable bearing surface while maintaining flexibility
• Reduced maintenance requirements due to durable 316 stainless steel material that resists wear and degradation

Professional Applications & Engineering Value

This M4 external tooth lock washer delivers critical vibration-resistant performance in demanding industrial applications where fastener security is paramount. Engineered from 316 stainless steel, it provides superior corrosion resistance in chemical processing, marine environments, and food processing equipment where moisture and corrosive agents are present. The external tooth configuration creates multiple biting points that dig into both the fastener head and base material, effectively preventing rotational loosening caused by machinery vibrations, thermal cycling, or dynamic loads. This DIN 6797 compliant design ensures reliable performance in automotive assemblies, electrical enclosures, and precision machinery where consistent clamping force must be maintained. The metric dimensions (4.3mm ID, 8mm OD) provide exact compatibility with M4 fasteners while the thin profile (0.4-0.6mm) accommodates space-constrained applications without compromising locking effectiveness.

Specification Summary & Compliance

This external tooth lock washer features precision dimensions of 4.3mm internal diameter and 8mm external diameter with thickness ranging 0.4-0.6mm, specifically engineered for M4 fastener applications. Manufactured in compliance with DIN 6797 standards for dimensional accuracy and performance requirements. The component is fully RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant (including 233 SVHCs as of 01/17/2023), meeting the latest environmental and safety regulations for industrial components. Constructed from 316 stainless steel for corrosion resistance and durability in demanding service conditions.