Difference between stainless steel V2A and V4A

We supply many of our stainless steel Auto-Lok nuts in a choice of two grades A2 and A4

A2 Version refers to V2A also known as 1.4301 or AISI 304

A4 Version refers to V4A also known as 1.4404 or AISI 316L

There are different grades of stainless steel. This means that under normal conditions, these types of steel are corrosion resistant.

Both :

- Offer excellent levels of corrosion resistance 

- Renowned for their durability and sustainability

Why self locking Auto-lok nuts do not loosen?

The self-locking Auto-lok nuts have different mechanism to avoid loosen.

The different  mechanism of self-locking resists vibrations and  and create a self-locking feature in the Auto-lok nuts.

More about ALNvsr Vertical slotted ring self locking Auto-Lok nut?

The  action of ALNvsr -  Vertical slotted ring self-locking Auto-lok nut is the spring ring tightens the tapping diameter at the slots of the nut body.

The engagement of the screw in the upper part of the nut moves the split parts of the nut body apart. By reaction, the spring ring creates a pressure that generates a tightening torque immobilizing the nut on the thread of the screw.

Some advantages

More about ALNhsr Horizontal slotted ring self locking Auto-Lok nut?

The ALNhsr - horizontal slotted ring self-locking Auto-lok nut is manufactured with a stainless steel spring insert. As the nut is fixed on the screw thread, the stainless steel spring insert secures with the base of the screw thread and expands upwards. This gives the nut a lower installation torque compared to other types of self-locking nut, especially those of the deformed thread type.

The ALNhsr - horizontal slotted ring self-locking Auto-lok Nut withstands vibration and loosening since the insert moves downwards and is ‘pulled’ into closer contact with the screw thread by the upwards anti-clockwise rotation of the nut body. This also gives a very effective interfering fit between the threads of the nut and of the screw. 


What is the difference between an Auto-Lok nut and the part number I requested?

The requested part and suggested alternative Auto-lok nut part number will be fully interchangeable with the thread. Since every part number is different, and you might have enquired for a discontinued or obsolete part, we need to verify with engineering to double check the compatibility.

Your sales rep can give you full confirmation about following properties of the part:

  • Form
  • Fit
  • Functionality
  • Material and Finish
  • Made according to the same quality and standard
  • Guaranteed same prevailing torque
  • Identical corrosion resistance

Please contact us for additional information or a quote.

How do self-locking nuts go on?

The self locking Auto-Lok Nut can be assembled with the locking element leading onto the male thread.


Are self-locking nuts one time use or reusable?

The self locking Auto-Lok nuts are reusables.

The auto lok-nuts combine both extreme vibration resistance with re-usability so you can rely on them time and time again.

The reusability will vary depending on the type auto lok nut type, the application and the use.

The Auto Lok nut is Re-usable up to 5 times with no performance loss according to ISO2320.

You can re-use them up to 15 times, ideal for maintenance purposes.



Do you have DAH nuts in steel CL8?


Yes, we have the Autolok-nut alternatives to the Metric Coarse Snep All Metal Self Locking Nut DAH nuts Seel CL8

For the part DAHM12X175CL8 we have the Autolok-nut ALNdM12x175CL8 with the same dimension.

For the part DAHM18X250CL8 we have the Autolok-nut ALNdM18x250CL8 with the same dimension.

For the part DAHM27X300CL8 we have the Autolok-nut ALNdM27x300CL8 with the same dimension.

Please find below the alternatives for DAH nuts in steel CL 8

DAH nuts CL8



What is a self locking auto-lok nut used for?

A self locking auto-lok nut is used for preventing loosing in vibration in applications:

Generally used in: Industry, Windmill, Automotive Industry, Rail, Aerospace, Agricultural machines,