Buy Hex Keys & Allen Wrenches Online in Australia
What is an Allen key?
An Allen key — also called a hex key or Allen wrench — is a hand tool with a hexagonal cross-section used to drive socket head fasteners such as socket head cap screws, button head screws and grub screws. The hex tip engages the matching hex socket in the fastener head. AIMS Industrial stocks Bondhus, Wiha, Stahlwille, Ko-Ken and Champion hex keys in L-key, T-handle, folding and ball-end formats across metric and imperial sizes.
What are the main types of Allen keys?
L-keys are the classic shape with a long arm for access and a short arm for torque. Ball-end L-keys allow entry at up to 25-30 degrees off-axis for confined spaces. T-handle hex keys deliver more torque and are faster for repetitive driving. Folding sets carry multiple sizes in a pocket-friendly magazine.
How do you choose the right Allen key size?
Match the hex tip size to the socket in the fastener head — common pairings are M5 cap screw to 4mm hex, M6 to 5mm, M8 to 6mm, M10 to 8mm and M12 to 10mm. Imperial hex keys (1/4", 5/16", 3/8" etc.) are used on imperial fasteners; metric and imperial sizes are not interchangeable.
Hex Key + Allen Wrench Selection — Quick Reference
Hex keys (Allen wrenches) drive internal hex socket fasteners — SHCS + button head + grub screws + countersunk socket screws. Selection turns on format (L-key vs T-handle vs folding set), tip type (ball-end vs hex), material grade, and size range (metric + imperial).
| Format | Best For | Common Spec |
|---|---|---|
| L-Key (Standard Allen) | Workshop default — pocket + bench use | 0.7mm – 19mm metric, 0.028" – 3/4" imperial |
| L-Key Ball-End | Access at angles — up to 25° off-axis | Less torque capacity than hex tip, useful for access |
| T-Handle | High-torque application + production speed | Bondhus + Wiha T-handle sets, sliding T versions |
| Long-Arm L-Key | Deep recess + behind-obstruction access | Extended shaft, ball-end usually included |
| Folding (Pocket) Set | Mobile tradies + pocket-carry | Multi-size in folding magazine — Wiha + Bondhus |
| Torx + Hex Combo Set | Mixed-fastener environments — automotive + electronics | Combined T-handle stand |
| Hex Power Bit (1/4" Hex Shank) | Driver + impact gun use | For impact drivers + cordless drills |
| Hex Socket (Drive) | Torque wrench + socket-drive use | 1/4", 3/8", 1/2" drive options |
Quality matters: Premium brands (Bondhus ProGuard, Wiha) hold +/-tolerance tight enough that the key fully seats in the socket without rounding. Cheap hex keys are slightly oversize + round out the screw socket. Size matching: M5 SHCS = 4mm hex | M6 = 5mm | M8 = 6mm | M10 = 8mm | M12 = 10mm. Brands: Bondhus, Wiha, Stahlwille, Ko-Ken, Champion. Companion: hex power bits, SHCS, hand tools.
Hex Keys and Allen Wrenches
Hex keys — also known as Allen keys or Allen wrenches — are one of the most commonly used hand tools in engineering and maintenance. AIMS carries an extensive range from premium brands including Bondhus, Wiha, Stahlwille, Ko-Ken and Champion, covering individual keys, folding sets and T-handle sets in both metric and imperial sizes.
Key Brands
Bondhus
Bondhus is a benchmark brand for hex keys in professional workshops. Their ProGuard-finished keys resist corrosion and are colour-coded for quick size identification. Available in ball-end L-wrench style, T-handle and long-arm versions, the Bondhus range covers metric and imperial in both individual and set formats.
Wiha and Stahlwille
Wiha and Stahlwille represent the premium German-engineered end of the range. Wiha hex keys are precision ground and hardened for close-tolerance fasteners and high-torque applications. Stahlwille tools are favoured in automotive and aerospace environments where dimensional accuracy and durability are critical.
Ko-Ken
Ko-Ken hex keys offer high-quality Japanese manufacturing with tight dimensional tolerances, popular in precision assembly and maintenance applications.
Types and Styles
L-Wrench (Short and Long Arm)
The classic L-wrench is the most versatile format. The short arm provides torque; the long arm accesses fasteners with limited clearance. Ball-end versions allow entry at up to 25–30 degrees off-axis, useful in confined spaces.
T-Handle Hex Keys
T-handle hex keys deliver more torque than L-wrenches and are faster to use repetitively. Preferred for production work, assembly lines and anywhere a large number of the same fastener needs driving in quick succession.
Metric vs Imperial
AIMS stocks both metric (mm) and imperial (inch/AF) hex key ranges. Most modern machinery uses metric fasteners, but imperial is still common in older equipment, American-made machinery and plumbing hardware. When ordering, confirm the drive size needed — a 1/4" AF fastener and a 6mm hex look similar but are not interchangeable.
People Also Ask — Hex Keys and Allen Wrenches
Q: What's the difference between metric and imperial hex keys?
Metric hex keys are sized in millimetres (1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm, 6mm, 8mm, 10mm common workshop sizes). Imperial hex keys use fractional inches (1/16, 5/64, 3/32, 1/8, 3/32, 5/32, 3/16, 7/32, 1/4, 5/16, 3/8 etc). The two systems aren't interchangeable — using an imperial key in a metric socket (or vice versa) damages the fastener. Most workshops keep both sets.
Q: Should I buy L-shape, T-handle, or ball-end hex keys?
L-shape is the workshop standard — compact, fits most kits, two leverage options (short and long arm). T-handle gives better speed and torque control for repetitive driving. Ball-end versions can engage at angles up to 25 degrees off-axis — useful for tight access where straight engagement isn't possible. Each has a place; many workshops keep all three styles in common sizes.
Q: What's a torx hex key and how is it different?
Torx (or 6-lobe) drives use a six-pointed star pattern instead of a hex shape — they engage the screw recess more positively and resist cam-out at higher torque. Torx and hex aren't interchangeable. Modern automotive, electronics, and aerospace applications increasingly use Torx; workshop machinery often still uses hex. Identify the screw drive pattern before selecting the key.
Q: What size hex key fits an M8 socket head cap screw?
M8 socket head cap screws use a 6mm hex key. Standard metric pattern: M3=2.5mm, M4=3mm, M5=4mm, M6=5mm, M8=6mm, M10=8mm, M12=10mm, M14=12mm, M16=14mm. Button head and low-head cap screws sometimes use a smaller hex (M8 button head often uses 5mm). When unsure, try the next size up if the smaller one is sloppy in the socket.
Q: Why do my hex keys keep rounding off?
Common causes: wrong size key in the socket (slightly undersize cams the corners), key is worn round from heavy use (replace), off-axis engagement when straight engagement is needed (use ball-end if access is restricted), or driving at too high a torque for the key's hardness (quality hardened hex keys handle more torque than budget keys). For high-torque work, use T-handle hex keys with better leverage.