3/8" Internal Tooth Lock Washer, Stainless Steel 400 Series

Manufactured from 400‑series stainless steel, this 3/8" internal tooth lock washer is designed to help prevent loosening caused by vibration and movement. The internal teeth bite into the underside of the fastener head and the mating surface, providing secure locking action while maintaining a low‑profile installation. Suitable for automotive, electrical, and general‑purpose inch‑series applications where reliable locking performance and moderate corrosion resistance are required.