Combination spanner for car repair
Updated: 22 October 2026
The sump plug looks like every other bolt, and the set in the basket says 6–19 mm. A combination spanner for car repair on a recent UK car is metric, and the size is the width across the flats, not the M number on the thread. A classic can be AF or Whitworth, and a near metric size will round it. The [combination spanner comparison](/hub/hand-tools/combination-spanner) is the listings. Peter F., DIY and tools editor, wrote it on 22 October 2026 from Haynes, Hagerty UK and those listings, not from a test of your car. A qualifying purchase can earn a commission at no extra cost to you.
The sump plug looks like every other bolt, and the set in the basket says 6–19 mm.
The sump plug looks like every other bolt, and the set in the basket says 6–19 mm. A combination spanner for car repair on a recent UK car is metric, and the size is the width across the flats, not the M number on the thread. A classic can be AF or Whitworth, and a near metric size will round it. The combination spanner comparison is the listings. Peter F., DIY and tools editor, wrote it on 22 October 2026 from Haynes, Hagerty UK and those listings, not from a test of your car. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | 16 mm | 19 mm | Ring | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  BGS BGS 1197 12-piece combination set | No | Yes | Plain, DIN 3113-A | 8.1 | about £12.80 | View offer |
| Alternative |  Qnkaa Qnkaa 12-piece ratchet combination set | Yes, in 8–19 mm | Yes | 72-tooth, nut must turn | 6.8 | about £29.95 | View offer |
| Best value |  Hilka Hilka 17161102 11-piece metric set | No; 15 mm is in | Yes | Plain, no standard | 7.6 | about £8.68 | View offer |
On this page
A recent UK car is a metric job
Haynes says virtually all cars of the last 30 years are metric. If you are servicing a daily driver from the 1990s onward, start with millimetres. AF and Whitworth belong to older machinery. A metric roll is right for a 2015 hatchback. It is wrong as the only set for a 1960s Mini. The ring is the end Haynes wants on the car, because the open jaw slips. That motion, including the ban on a pipe, is how to use a combination spanner. None of these sets is a Whitworth set, and none sets wheel-nut torque.
The sizes that come up, and the M10 split
For a basic modern-car set, look for 8, 10, 13, 17 and 19 mm, and keep 15 and 16 mm in reach.
M10 is the thread, not the spanner. MLC’s chart, following ISO 4014 and ISO 4017, puts a current M10 hex at 16 mm across the flats, and the older DIN head at 17 mm. M12 is 18 mm on the ISO head and 19 mm on the older DIN head. If you only own 17 mm, the 16 mm head gets a rocking pull. The buying order for material and DIN stays on the buying guide.
AF and Whitworth are different sets
AF means the opening, in inches. Hagerty UK is explicit that 13 mm is not 1/2 inch AF. A metric set will damage those bolts while feeling as if it almost fitted. Whitworth is a second system, and the mark is the thread, not the jaw. Wheels Alive gives the figure: 1/2 W is about 0.919 inches across the flats, not 1/2 inch and not 13 mm. Kamasa’s 4446 set is a Whitworth combination run, listed at £45.28 including VAT. It is not in this folder. Mini Spares’ 32-piece set is AF plus metric, not Whitworth. A classic Mini can carry Whitworth, AF, or a mix. Identify the head before the corners go.
What that means for the sets in this comparison
Qnkaa, at £29.95, lists every millimetre from 8 to 19, including 16 mm and 19 mm, if the nut already turns. BGS 1197, at £12.80, prints 19 mm and misses 16 mm. Hilka 17161102, at £8.68, prints 15 mm and 19 mm and skips 16 mm. DISEN prints 16 mm and has no 19 mm. Neilsen says 6 mm to 32 mm and does not itemise. The conditional pick is best combination spanner sets.
Stop if you cannot torque brakes, steering, suspension or wheel nuts, or support the car on rated stands. A combination spanner does not replace a torque wrench, and 17 mm is not every M10.
Common questions
Are UK cars metric now?
For virtually all cars of the last 30 years, Haynes says yes. A modern hatchback takes metric combination spanners. AF and Whitworth show up on older British cars and on parts that were never converted. The year and the head in front of you decide, not the aisle the set was sold in.
Which millimetres should a basic car set include?
Look for 8, 10, 13, 17 and 19 mm, and keep 15 and 16 mm in reach. A set that skips 16 mm fails a current ISO M10 head. A set that skips 19 mm fails many older M12 nuts. Measure one fastener on your car before you treat any published list as complete. Auto Express wanted those core sizes in 2022 on other brands, not on these ASINs.
Is 17 mm the spanner for every M10?
No. M10 is the thread. MLC’s chart gives 16 mm for current ISO heads and 17 mm for the older DIN head. Both are still on UK cars. Try each for a seat with no rock, and use the one that does not move on the flats. Pulling 17 mm onto a 16 mm head rounds it. The thread stamp will not warn you.
Why do I still see 19 mm on an M12 nut?
Older DIN hexagons for M12 are 19 mm across the flats. The ISO size is 18 mm. A bracket nut can keep the 19 mm head long after the thread is called M12. BGS includes 19 mm and not 16 mm. DISEN includes 16 mm and not 19 mm. If your nut measures 19 mm, stopping at 18 mm leaves you one size short.
Will 13 mm do for a 1/2 inch AF bolt?
No. Hagerty UK states that 13 mm is not 1/2 inch AF. The ring may start to fit and then rock, and a longer pull makes the rounding worse. The same ban applies to Whitworth. Wheels Alive puts 1/2 W at about 0.919 inches across the flats, so neither 13 mm nor 1/2 inch AF is that jaw.
When do I stop and use a garage?
Use a torque wrench for wheel nuts and for brake, steering or suspension fasteners that specify a figure. A combination spanner cannot show that figure. Use a garage if you cannot support the car on rated stands, if the next step is heat or cutting, or if the corners are already round. These listings are hand spanners for a hex you can see.
Related pages
Sources
Sources from the research digest, last checked on 22 October 2026.
- HSE, PUWER overview (retrieved 22.10.2026)
- HSE, INDG229 Using work equipment safely (retrieved 22.10.2026)
- HSE, repetition and upper-limb disorders (retrieved 22.10.2026)
- ISO 1711-1:2019 (retrieved 22.10.2026)
- Consumer Rights Act 2015, section 22 (retrieved 22.10.2026)
- nidirect, buying goods and services (retrieved 22.10.2026)
- Hagerty UK, choosing spanners for DIY (retrieved 22.10.2026)
- Wheels Alive, threads, spanners and things (retrieved 22.10.2026)