Buy Open End Wrenches Online in Australia
Open End Wrench Quick Reference — Styles & Sizes
Open end wrenches engage two flats of a hex fastener through U-shaped jaws — slide-on/slide-off rather than lift-over. The right pick for fasteners with restricted access, fittings on hydraulic and pneumatic lines, and situations where a ring spanner or socket can't fit. AIMS stocks Stahlwille, Bahco, Maxigear and Goliath in metric and imperial sizes from M5 (8 mm AF) up to large industrial sizes.
| Wrench Style | Best For | Common Sizes | Brand Examples |
|---|---|---|---|
| Double Open End | Workshop default — different size at each end | 6×7, 8×9, 10×11, 12×13, 14×15, 17×19, 22×24, 27×32 mm | Stahlwille, Bahco, Maxigear, Goliath |
| Combination (Open + Ring) | Open end for access + ring end for final torque | Matched pairs — single size each end (8 to 32 mm metric) | Stahlwille, Bahco |
| Open End Set | Workshop kit covering common range | 6-22 mm (basic), 6-32 mm (full), 1/4"-1-1/4" (imperial) | Bahco, Maxigear sets |
| Long-Pattern Open End | Higher torque, harder access | Same flat sizes as standard — longer handle | Stahlwille extended-length range |
| Stubby (Short) | Tight clearance where standard length won't fit | 6-22 mm typical | Bahco stubby range |
| Angled Head (15° / 30° offset) | Tight clearance + access angle adjustment | Common metric sizes 8-24 mm | Stahlwille angled-head range |
Most metric sizes follow standard AF dimensions: M5=8 mm AF, M6=10, M8=13, M10=17, M12=19, M14=22, M16=24, M18=27, M20=30, M24=36. For AF/imperial cross-reference and shifter alternatives, see our spanner size chart. For ring spanners and socket alternatives, see ring spanners and sockets.
Open End Wrenches and Spanners
An open end wrench (also called an open end spanner) has U-shaped jaws that engage two flats of a hex fastener, allowing the wrench to slide on and off without lifting over the fastener head. That makes them the right tool for fasteners with restricted access, fittings on hydraulic and pneumatic lines, and any situation where a ring spanner or socket can't be lifted on. AIMS Industrial stocks open end wrenches and double-ended sets in metric and imperial sizes from the brands trade workers actually use.
The styles in our range
- Double open end spanners — different size at each end, the everyday workshop choice
- Combination wrenches — open end on one end, ring on the other, in matching sizes
- Open end wrench sets — matched sets covering the common metric or imperial range
- Long-pattern open end — extended handle for higher torque and harder access
- Stubby (short) open end — for tight clearance work where standard length won't fit
- Angled-head open end — 15° or 30° offset head for clearance over adjacent obstacles
Where open end earns its place
- Hydraulic and pneumatic fittings — JIC, ORFS, NPT, and BSP fittings where the line itself prevents lifting a ring spanner over
- Fuel and brake line connections — flare fittings on automotive and industrial work
- Compression fittings — plumbing and gas line connections
- General workshop work — wherever a fastener is in a position that ring or socket can't reach
Open end versus ring versus combination
Open end is fastest on and off but transmits less torque safely than ring spanners (the open jaw geometry means more grip pressure is needed, and the wrench is more likely to round a fastener under high load). For breaking a tight fastener, use the ring or socket end of a combination wrench; for the runout once it's loose, switch to open end for speed.
Brands stocked at AIMS
Bahco is the trade workhorse — solid quality at a sensible price, the brand most Australian tradies eventually settle on. Stahlwille and Wiha cover the precision and premium end where European-spec or particularly high-quality work is the priority. All three brands are chosen because the jaw tolerances stay tight after years of use, the chrome finish holds up, and the steel doesn't crack under load.
Sets versus singles
A 12- to 14-piece metric or imperial set typically covers the daily-used range (8mm-22mm metric is the everyday workshop range). Singles let you replace the size that's seen the most use, or top up a set with non-standard sizes. Most workshops end up with one base set plus singles for specific jobs.
Need help speccing wrenches for a trade or workshop? contact our team — we'll match brand, size range, and pattern.
People Also Ask — Open End Wrenches
Q: What is the difference between an open end wrench and a ring spanner?
An open end wrench has U-shaped jaws that engage two flats of a hexagonal fastener from the side — making it the right choice for restricted overhead access, hydraulic and pneumatic fittings, and fasteners where a ring spanner can't be lifted on from above. A ring spanner fully encircles the fastener head for better torque transmission and resistance to rounding but requires axial clearance to place over the fastener.
Q: What are the across-flats (AF) sizes for common metric fasteners?
Standard metric fasteners use these AF sizes: M5 = 8 mm, M6 = 10 mm, M8 = 13 mm, M10 = 17 mm, M12 = 19 mm, M14 = 22 mm, M16 = 24 mm, M18 = 27 mm, M20 = 30 mm, and M24 = 36 mm. Double open end spanners cover two sizes at once — for example 8×9, 10×11, 12×13, and 17×19 are common combinations.
Q: What is a double open end spanner?
A double open end spanner has a different jaw size at each end, covering two fastener sizes in one tool — the standard workshop choice for general mechanical work. The open-jaw design suits fittings on hydraulic lines, pipe connections, and fasteners where restricted access prevents a ring spanner or socket from being used.
Q: When should a stubby open end spanner be used?
A stubby (short-pattern) open end spanner is designed for tight clearance situations where the standard-length handle won't fit — inside engine bays, within equipment housings, or wherever clearance restricts handle swing. The short handle limits maximum torque, so stubby spanners suit moderate-torque fasteners in confined locations rather than high-torque structural joints.
Q: What is a long-pattern open end spanner?
A long-pattern (extended-length) open end spanner has a longer handle than the standard pattern, providing additional torque and improved access to deeply recessed or hard-to-reach fasteners. The same jaw sizes apply as standard; the longer handle reduces hand fatigue on repetitive fastener work and allows more leverage on stubborn fasteners without resorting to an extension bar.