Hillman 126491 1/4-20 Zinc Plated Steel Stop Lock Nut-8PK

SAE Stop lock nut in zinc-plated finish, features steel construction. This coarse threaded nut with nylon insert resists loosening under vibrations and torque. The nylon washer tightly locks the nut with bolts.
Nylon insert lock nut is suitable for applications where heavy vibration is found and when a tight frictional fit is required
Allows installing and removing with hand tools
Spin freely until the nylon washer engages the threads of the mating part
Offers moderate corrosion resistance
Use with washer for effective locking action