Lock Washer

The Black Oxide External Tooth Lock Washer is a durable and reliable anti-loosening fastening accessory designed to prevent bolt and nut connection loosening under vibration and dynamic load in machinery, automotive, electrical equipment and general industrial assembly applications. Featuring a spring steel washer body with evenly distributed external serrated locking teeth, this lock washer delivers strong elastic tension and bite force after tightening, effectively stopping fasteners from rotating loose and maintaining stable clamping force for long-term secure connection.

Manufactured from high-quality high carbon spring steel or 65Mn spring steel, the external tooth lock washer offers excellent elastic toughness, impact resistance and long-term fatigue durability. The surface adopts professional black oxide treatment with additional anti-rust oil coating, forming a uniform protective layer that resists moisture and oxidation, while keeping a neat matte black appearance that avoids reflection interference for precision equipment assembly. These protective finishes extend service life and maintain stable elastic performance under indoor heavy-duty operating environments.

The evenly arranged external serrated teeth design creates strong bite force with the connected metal surface after the fastener is tightened, while the spring steel body provides continuous elastic tension to offset the loosening force caused by vibration and thermal expansion and contraction. This structure effectively reduces the risk of fastener loosening and falling off, greatly improving overall equipment operational safety and reducing long-term maintenance costs. The standard inner diameter and outer tooth size perfectly match all kinds of standard bolts and nuts, suitable for automatic assembly line production.

External tooth lock washers are widely used for mechanical equipment assembly, automotive chassis and engine parts, electrical control cabinet fixing, furniture hardware connection, industrial valve and pump assembly, and all kinds of bolt-nut anti-loosening linkage systems. Their reliable anti-loosening performance and cost-effective design make them the standard universal anti-loosening accessory for all industrial and daily assembly projects requiring stable long-term fastening.

We provide OEM and ODM manufacturing services and support custom production according to customer drawings, samples, or special specification requirements. Customized inner diameters, outer tooth sizes, thicknesses, material grades and customized packaging options are available to meet unique project demands. Private labeling and custom branding printing services are also supported for hardware distributors, machinery factories, automotive parts manufacturers and equipment assembly plants.

Each black oxide external tooth lock washer is manufactured under strict fastener quality control standards and undergoes comprehensive dimensional inspection, elastic performance test and surface anti-corrosion inspection before shipment to ensure dimensional accuracy, consistent elastic toughness and uniform qualified black oxide surface finish for every product batch.