High-Quality Internal Tooth Lock Washers

What is an Internal Tooth Lock Washer?

An internal tooth lock washer is a highly specialized, tension-inducing fastener engineered with aggressive locking teeth positioned along the inner diameter of the ring. Designed to deeply grip the threads and underside of a screw or bolt head, these washers actively prevent back-off rotation and looseness without exposing sharp edges. Manufactured from premium, industrial-grade materials, they provide an exceptionally secure, vibration-resistant hold while maintaining a clean, perfectly smooth exterior profile.

Mechanical Advantages and Industrial Applications

Because they conceal their locking mechanism beneath the fastener head, internal tooth lock washers offer several critical structural advantages for complex assemblies:

• Anti-Rotational Grip: The internal teeth physically bite into both the fastener and the mating surface, creating a highly effective locking action that is essential for heavy load-bearing, high-shock, and severe vibration-absorbing applications.
• Smooth, Snag-Free Edge: Unlike external tooth washers, the completely smooth outer diameter actively prevents friction, binding, or snagging with nearby moving parts, electrical wiring, or adjacent machinery. This heavily protects the surrounding assembly and maintains a highly professional aesthetic.
• Small Head Compatibility: Because the locking teeth are centralized and hidden, these washers are the absolute industry standard for safely securing small head fasteners (such as fillister or cheese head screws) where protruding external teeth would be structurally or visually unacceptable.

Custom Manufacturing and Expert Finishing

For over 25 years, U-Bolt-It has been a leading distributor and manufacturer of high-quality washer solutions. We maintain a massive, full-line inventory of internal tooth lock washers readily available in highly durable zinc and corrosion-resistant stainless steel. We expertly accommodate both standard sizing and fully custom dimensions, scaling effortlessly from rapid short runs to full-scale production runs. Furthermore, our facility offers advanced custom plating, coating, and finishing services to ensure your washers meet your exact environmental and operational requirements.

Request a Quote Today

Have a question about our manufactured internal tooth lock washers or need help selecting the perfect custom finish for your vibration-heavy application? Contact our team by using our secure online form to submit your project details. You can also give us a call today to speak directly with our experienced fastener specialists. We are completely committed to ensuring you receive the exact product you need with quick, on-time delivery. We look forward to speaking with you!