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Tools · ISO 2936 · Application guide

What Are Hex Keys (Allen Keys) Used For?

Typical applications, the industries that specify hex keys (allen keys), and how to choose the right size, material and finish for the joint.

Hex Keys (Allen Keys) are used for installing, adjusting or servicing the assembly rather than forming part of it. They are manufactured to ISO 2936, and selection is driven by the nominal size, the fit and tolerance the assembly requires, and the service environment.

Primary duty
Installing, adjusting or servicing the assembly rather than forming part of it
Governing standard
ISO 2936
Nominal size range
0.7 mm to 60 mm
Category
Tools

Application notes are general engineering guidance. Verify the property class and any approval requirement against your own design calculation.

What Are Hex Keys (Allen Keys) Used For? application image

The primary duty of Hex Keys (Allen Keys) is installing, adjusting or servicing the assembly rather than forming part of it. Below: the sectors that specify them in volume, the checklist used to select the right size and material for the application, installation notes, and the known limits of the type. Stocked across roughly 0.7 mm to 60 mm, they cover general to heavy-duty work.

Typical Applications for Hex Keys (Allen Keys)

The most common settings where these are specified:

  • General machine building: fastening covers, brackets, motors and sub-assemblies on production equipment.
  • Maintenance & repair (MRO): a stocked size for servicing existing plant where the original fastener spec must be matched.
  • Fabrication & metalwork: bench and on-site assembly of steel frames, enclosures and weldments.

How to Specify Hex Keys (Allen Keys) for Your Application

  • Size: Select on nominal size, and confirm it against the mating feature in the assembly. This product spans 0.7 mm–60 mm; check the full table below for the exact dimensions of each size.
  • Material: Choose the material and finish for the service environment — plated steel for general use, stainless for corrosion resistance.
  • Environment: For damp, coastal or chemical exposure prefer A4/316 stainless or a suitable coating; indoors, plated steel or A2 is usually sufficient.
  • Standard: This product is supplied to ISO 2936. Quoting the standard on your order guarantees interchangeable dimensions between suppliers.

Where Hex Keys (Allen Keys) Are Not the Right Choice

Match the fastener to the load, environment and whether the joint must be reopened; the wrong class or style is the usual cause of joint failure.

Technical Drawing

Customize the parameters below — every spec field is editable, and the drawing redraws to match the values you choose. Changing the size will snap the other fields to that size's standard values; you can then override any individual value.

Sends the selected values to the quote form below.

Request a Quote

The form below follows the current technical drawing configuration. Change the drawing values above and the request details update automatically.

Request a Quotation

Specification
Business Information

Dimensions & Specifications (ISO 2936)

Wrench size s (mm)Common bolt sizesShort leg (mm)Long leg (mm)Reference standard
0.7M12851ISO 2936 / DIN 911
0.9M1.12856ISO 2936 / DIN 911
1.0M1.23256ISO 2936 / DIN 911
1.3M1.63663ISO 2936 / DIN 911
1.5M24071ISO 2936 / DIN 911
2.0M2.55090ISO 2936 / DIN 911
2.5M356100ISO 2936 / DIN 911
3.0M463112ISO 2936 / DIN 911
4.0M571125ISO 2936 / DIN 911
5.0M680140ISO 2936 / DIN 911
6.0M890160ISO 2936 / DIN 911
7.0---100180ISO 2936 / DIN 911
8.0M10112200ISO 2936 / DIN 911
9.0---112200ISO 2936 / DIN 911
10.0M12125224ISO 2936 / DIN 911
12.0M14140250ISO 2936 / DIN 911
14.0M16160280ISO 2936 / DIN 911
17.0M20180315ISO 2936 / DIN 911
19.0M22200355ISO 2936 / DIN 911
22.0M24224400ISO 2936 / DIN 911
24.0M27250450ISO 2936 / DIN 911
27.0M30280500ISO 2936 / DIN 911
32.0M36315560ISO 2936 / DIN 911
36.0M42355630ISO 2936 / DIN 911
41.0M48400710ISO 2936 / DIN 911
46.0---450800ISO 2936 / DIN 911
50.0---500900ISO 2936 / DIN 911
55.0---500900ISO 2936 / DIN 911
60.0---5601000ISO 2936 / DIN 911
Inside the plant

Manufactured in our own plant

This part is cold-formed, threaded, heat-treated and finished in-house. The stages below are where its class and finish are actually decided.

  1. Wire rod feeding into a cold heading machine
    01

    Cold heading

    Wire rod is drawn to size and cold-formed into blanks. Forming rather than cutting keeps the grain flow continuous around the head, which is where a bolt is most likely to fail.

    Head dimensions and under-head radius checked at set-up and per shift.

  2. Thread rolling machine producing bolt threads
    02

    Thread rolling

    Threads are rolled between hardened dies rather than cut. Rolled threads are stronger in fatigue than cut threads and hold pitch and flank angle far more consistently across a batch.

    Go / no-go ring gauges to ISO 965 tolerance class 6g.

  3. Baskets of bolts staged for heat treatment
    03

    Heat treatment

    Quench-and-temper brings carbon and alloy steel to the property class ordered — 8.8, 10.9 or 12.9 — with the furnace charge tracked so a finished lot can be traced back to it.

    Core hardness and tensile tested per lot to ISO 898-1.

  4. Zinc plated bolts in a treatment basket
    04

    Surface treatment

    Zinc, zinc-nickel, hot-dip galvanizing, black oxide, phosphate and Dacromet, selected against the service environment rather than against the price list.

    Coating thickness and neutral salt spray hours to ISO 9227.

Frequently Asked Questions

What are Hex Keys (Allen Keys) used for?

Installing, adjusting or servicing the assembly rather than forming part of it. They are supplied to ISO 2936.

Which industries use Hex Keys (Allen Keys)?

They are commonly specified in general machine building, maintenance & repair (mro) and fabrication & metalwork, among other sectors.

How do I choose the right size of Hex Keys (Allen Keys)?

Select on nominal size and on the fit the assembly requires. This product is available from 0.7 mm to 60 mm; the full dimension table on this page lists each size.

Are Hex Keys (Allen Keys) made to a recognized standard?

Yes — they are manufactured to ISO 2936, so dimensions are interchangeable between suppliers when you quote the standard on your order.

Can I get a quote for Hex Keys (Allen Keys) in the size and material I need?

Yes. Use the technical drawing and quote form on this page to set the size and options, then send the exact configuration to our team for pricing and lead time.