S-90900A111 0.22" ID x 0.421" OD ASME B18.21.1 Countersunk External-Tooth Lock Washers
Countersunk External-Tooth Lock Washers
Image may differ from product. See technical specification for details.
Basic Information
Dimension Parameters
Material & Strength Parameters
Installation & Application Parameters
Finish & Compliance Parameters
Geometric Parameters
Special Type Parameters
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Key Features & Benefits at a Glance
- Superior vibration resistance through external tooth design that bites into mating surfaces, preventing loosening under dynamic loads
- Enhanced corrosion protection with 400 Series Stainless Steel construction, ideal for harsh industrial environments
- Optimized countersunk seating with 82° angle for flush mounting in countersunk screw applications
- Precise dimensional control with 0.22" ID and 0.421" OD ensuring perfect fit for No. 12 screws
- Exceptional durability backed by Rockwell C34 hardness for long service life under high stress conditions
- Industry-standard compliance meeting ASME B18.21.1 specifications for reliable performance
- Environmental responsibility with RoHS 3 and REACH compliance for safe use in regulated applications
Professional Applications & Engineering Value
This external tooth lock washer delivers critical vibration resistance in demanding applications where fastener security is paramount. The 400 Series Stainless Steel construction provides excellent corrosion resistance while maintaining the mechanical strength needed for industrial machinery, automotive assemblies, and electrical enclosures. The countersunk design with 82° angle ensures seamless integration with countersunk fasteners, eliminating protrusions that could interfere with moving parts or create safety hazards. The external teeth create multiple biting points that dig into both the fastener and substrate, distributing clamping force evenly and maintaining tension under extreme vibration conditions. This engineering solution addresses the common failure point of loosening fasteners in high-vibration environments, extending equipment lifespan and reducing maintenance downtime.
Specification Summary & Compliance
This precision external tooth lock washer features dimensional specifications of 0.22" internal diameter, 0.421" outer diameter, and thickness ranging 0.020-0.025" for No. 12 screw applications. Manufactured to ASME B18.21.1 standards with proper tooth configuration and material properties. The washer is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and regulatory acceptance for industrial use worldwide.
