All-metal double slotted self-locking nuts
Auto-Lok double slotted nuts provide low prevailing torque, high reusability and reliable all-metal locking for demanding industrial applications.
The Auto-Lok double slotted nut follows the familiar industrial hex nut form, but adds a slotted collar above the hexagon. Two slots are positioned one above the other so that, during tightening, the metal above the slots deforms slightly and grips the bolt thread on the flank — the area designed to carry the load.
This geometry creates a controlled prevailing torque and strong thrust resistance, while keeping the threads themselves reusable and free from crushing or damage. The nut can also be installed with the locking element leading onto the male thread first, depending on your preferred assembly method.
Key characteristics
- All-metal, reusable self-locking nut (no nylon inserts).
- Lower prevailing torque than many conventional lock nuts.
- Suitable for both high and low temperature environments.
- Locking performance unaffected by oil, petrol and most industrial liquids and vapours.
- Easy installation with standard hand or power tools, with or without a supporting face.
Standard finishes for Auto-Lok double slotted nuts include zinc and chromate passivation or self-colour for metric threads, and zinc or self-colour for other thread series. On request, we can supply special materials, finishes and custom designs to meet specific application, standard or corrosion requirements (subject to minimum manufacturing quantities).
Double slotted nut variants
Double Slotted Nuts — Standard
Standard double slotted Auto-Lok nut for general industrial and structural applications.
Double Slotted Nuts — Opposite
Opposite slot configuration for specific torque paths, access or assembly constraints.