100PCS 3/8" & 1/4" Internal Tooth Lock Washers, Stainless Steel Internal Serrated Star Washers for Bolt and Screw Fastening (1/4-Inch)

These internal tooth lock washers are designed to provide enhanced fastening security in mechanical and industrial applications. The internal serrated teeth generate spring force and increased friction between the fastener head and mounting surface, helping prevent loosening due to vibration or movement. Manufactured from stainless steel, these washers offer excellent corrosion resistance, strength, and durability for long-term performance. The precision-stamped design ensures consistent thickness and reliable load distribution. Suitable for use with 3/8-inch bolts and screws, these internal star lock washers are widely used in automotive repair, machinery assembly, electrical equipment, and construction projects.

• Internal Tooth Lock Washer Design. Internal serrated teeth create spring tension between the fastener head and contact surface, increasing friction and helping prevent loosening from vibration.
• Durable Stainless Steel Construction. Manufactured from corrosion-resistant stainless steel for long-term strength and reliability in indoor and outdoor environments.
• Anti-Vibration & Secure Fastening. Designed to improve rotational resistance and evenly distribute clamping force across connected components.
• Suitable for Bolts & Screws. Compatible with standard bolt and screw fastening applications across mechanical and industrial setups.
• Multiple Sizes Available. Available in different inner diameters to meet various fastening requirements. Please select the correct size from the variation options.