Grade 8 (C) Prevailing Torque (Stover) Lock Nut

Grade 8 (C) prevailing torque lock nuts, widely known as Stover nuts or top lock nuts, are all-metal lock nuts. The top threads are slightly distorted so they grip the bolt and resist loosening from vibration. With no nylon insert, they work at higher temperatures than nylock nuts and suit high-strength Grade 8 bolting. Ours are zinc plated and waxed for smoother installation.

Specifications

Type: all-metal prevailing torque (Stover / top lock)
Strength: Grade 8 (C)
Finish: zinc plated and waxed
Coarse (USS/UNC): 1/4"-20 through 1-1/2"-6
Fine (SAE/UNF): 1/4"-28 through 1"-14

Common Uses

Heavy equipment, trucks and trailers
Hot areas near engines and exhaust
High-vibration Grade 8 joints

FAQ

What is a prevailing torque nut?
It is a nut that resists turning even before it is tightened against anything. The distorted threads create friction against the bolt, so it locks on its own instead of relying on clamp load.

Stover nut or nylon insert nut?
Choose a Stover nut for heat, high strength or frequent removal. Choose a nylon insert nut for lighter duty and easier hand starting.

Free shipping on orders over $100, and orders placed before noon EST ship the same day. Purchase orders are accepted from government agencies, schools, hospitals, municipalities and companies with established credit with The Nutty Company, Inc.