The LOCK WASHER INTERNAL ZINC #10 INTERNAL TOOTHED is a hardened circular washer designed with inward-extending teeth that provide excellent grip and prevent loosening under vibration. Made from high-quality spring steel and coated with zinc, this washer offers superior durability and corrosion resistance, making it ideal for automotive and industrial applications where a neat appearance is essential. Its design allows the teeth to remain hidden under the screw head, ensuring a clean finish while maintaining reliable fastening performance.