S-91233A117 0.384" ID x 0.694" OD ASME B18.21.1 External-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance with external teeth that bite into mating surfaces to prevent loosening under dynamic loads
• Enhanced durability and corrosion protection through Black Oxide Steel construction with Rockwell C40 hardness
• Precise fit for 3/8" fasteners with 0.384" ID and 0.694" OD dimensions ensuring optimal installation
• Reliable performance in demanding applications thanks to compliance with ASME B18.21.1 standards
• Environmental and regulatory compliance meeting RoHS 3 and REACH requirements for safe industrial use
• Consistent thickness control between 0.032-0.040" for uniform clamping force distribution
• Optimized for inch system applications in mechanical assemblies requiring secure locking under vibration

Professional Applications & Engineering Value

This heavy-duty external tooth lock washer delivers critical vibration resistance in demanding mechanical systems where fastener loosening can lead to equipment failure. The Black Oxide Steel construction provides superior surface protection while maintaining the Rockwell C40 hardness necessary for repeated loading cycles. The external tooth configuration creates multiple biting points that dig into both the fastener head and mating surface, distributing clamping force evenly and maintaining tension under extreme vibration conditions. Engineered specifically for 3/8" screw applications with precise internal and outer diameters, this washer solves common industrial challenges in automotive, machinery, and structural assemblies where thermal cycling and dynamic loads compromise fastener integrity. The combination of material strength and tooth design ensures reliable performance in high-stress environments while meeting critical industry standards.

Specification Summary & Compliance

This external tooth lock washer features precision dimensions including 0.384" ID, 0.694" OD, and thickness ranging 0.032-0.040" for consistent performance with 3/8" fasteners. Manufactured to ASME B18.21.1 specifications for mechanical lock washers, it ensures dimensional accuracy and functional reliability. The product maintains full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its suitability for environmentally conscious industrial applications while meeting the latest substance restriction requirements.