Combi drill vs SDS
Updated: October 2026
A combi drill vs SDS decision shows up the week a UK house gives you a shelf and a concrete lintel. You can buy a rotary hammer for a picture hook, or you can burn a chuck drill on a lintel it was never stated to finish. This page separates those jobs for the Worx models in the [Worx drill comparison](/hub/drilling-and-accessories/worx-drill). Prices are the amazon.co.uk listings on 15 October 2026. The Products Compared editorial team did not measure joules in a lab. A qualifying purchase can earn a commission at no extra cost to you.
A combi drill vs SDS decision shows up the week a UK house gives you a shelf and a concrete lintel. You can buy a rotary hammer for a picture hook, or you can burn a chuck drill on a lintel it was never stated to finish.
A combi drill vs SDS decision shows up the week a UK house gives you a shelf and a concrete lintel. You can buy a rotary hammer for a picture hook, or you can burn a chuck drill on a lintel it was never stated to finish. This page separates those jobs for the Worx models in the Worx drill comparison. Prices are the amazon.co.uk listings on 15 October 2026. The Products Compared editorial team did not measure joules in a lab. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Mechanism | Torque or impact | Stated hard-material limit | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  WORX WORX WX370.1 | Combi hammer, 13 mm chuck | 50 Nm | Masonry 10 mm in the bullets | 9.2 | about £76.94 | View offer |
| Alternative |  WORX WORX WX381.9 Nitro | SDS rotary hammer, bare | 2.0 J | Concrete 22 mm, plus chisel | 9.2 | about £129.99 | View offer |
| Alternative |  WORX WORX WX391 | SDS rotary hammer, kit | 1.2 J | Concrete 13 mm | 8.6 | about £103.99 | View offer |
On this page
What each mechanism actually does
A Worx combi hammers with a rattling mechanism inside a 13 mm keyless chuck, and you still push. Bosch's DIY guidance calls that kind of hammer cam discs that need pressure from you, and it keeps tiles and timber off hammer mode. An SDS rotary hammer uses a piston to strike the bit, so the useful number is joules. Screwfix treats the combi as the all-rounder and the SDS as the tool for hard masonry. Data Power Tools notes that an SDS is a poor all-day screwdriver. BuildWiz's line that combi hammers sit under 1 joule is their rule of thumb, not a Worx measurement.
Brick plugs versus concrete
A brick plug is combi work inside the stated masonry figure. The WX370 bullets say 10 mm. uk.worx.com also says 13 mm, so plan on 10 mm until the manual agrees. Homebuilding treats harder, newer concrete as an SDS job. Ordinary plugs are on the Worx drill buying guide.
The Slammer sits between those jobs. The WX354 kit is £145.99 with two 2.0 Ah batteries, and the title claims 10 mm in reinforced concrete, with C30 in the bullets. The bare WX354.9 is £208.15 with no battery, and its reviews include early failures. Both are still 13 mm chuck drills at 60 Nm. Sixty newton metres is not 2.0 joules, and a Slammer is not SDS Plus.
WX391 or WX381.9
The smaller rotary hammer is the WX391, at £103.99. The bullets state 1.2 J and concrete and masonry up to 13 mm, with one 2.0 Ah battery and a charger in the box. Chisel mode is not stated. It is 4.3 from 10 reviews, and one review says the hammer cut out in a wall.
The larger hammer is the WX381.9, at £129.99 on amazon.co.uk and £142.99 on uk.worx.com. The bullets state 2.0 J, concrete up to 22 mm, and chiselling, with no battery in the box. It is 4.6 from 267 reviews. The spec table also prints 1.35 rpm and 2 Nm. Ignore those fields and use the bullets.
Bits, the adaptor, and screws
An SDS Plus bit does not belong in a 13 mm keyless chuck, and a round masonry bit does not belong in an SDS chuck if you want the piston blow. ITS states it directly: SDS bits need an SDS chuck. An adaptor with an SDS shank is for rotary drilling and driving, and hammer mode through that adaptor is a bad idea. The WX391 ships with that adaptor, and one UK review calls it clunky and unbalanced. The collar and the brick-plug sequence are on the how to use a Worx combi drill page.
When to pick which body
Use a combi when the week is screws and a few brick plugs. Use the WX391 when holes stay within 13 mm and you want a battery in the box. Use the WX381.9 when you need 22 mm or a chisel and you already have a pack. If both jobs are yours, own both tools. Do not read 60 Nm on a Slammer as 2.0 J.
Common questions
When is the hole a concrete or engineering-brick job?
Treat harder new concrete, a lintel, and engineering brick as SDS work, which is the Homebuilding line, and use an SDS-rated bit. In this set the WX391 states 13 mm at 1.2 J, and the WX381.9 states 22 mm at 2.0 J plus a chisel. The Slammer's 10 mm C30 claim is still a chuck drill. If the bit glazes and the hole does not deepen, stop and change tool.
Should you choose the WX391 or the WX381.9?
Choose the WX391 at £103.99 when the holes stay within 13 mm and you want the 2.0 Ah battery in the box. It has no stated chisel mode, and the review sample is 10 ratings, including one cut-out in a wall. Choose the WX381.9 at £129.99 when you need 22 mm or a chisel and you already own a PowerShare pack. The brand shop lists that bare tool at £142.99.
Can you chisel tiles or a chase with the combi?
A combi in this set does not offer a chisel mode. Hammer mode is for drilling with a masonry bit, and tile glaze stays off that mode. Chasing bricks for a socket is what WX381.9 reviewers describe, on a tool whose bullets include chiselling and angle adjustment. The WX391 bullets do not state a chisel. If the job is a chase, the combi is the wrong body.
Can you put an SDS bit in the 13 mm chuck?
Put an SDS Plus bit in an SDS chuck, not in the 13 mm keyless chuck. A round masonry bit in an SDS chuck will not take the piston blow properly. The WX391's adaptor is for rotary drilling and screwdriving, and one review says it unbalances the tool. Hammering through that adaptor is a bad idea. Keep a combi for screws.
Does an SDS replace the combi for flat-pack and screws?
No. An SDS is the concrete and chisel tool. It is a poor substitute for an afternoon of driving screws, which is why Data Power Tools says the two drills complement each other. Flat-pack, timber, and clutch-controlled screws stay on the combi. Buy the SDS when concrete or chiselling is the reason you are shopping, and keep the combi if that other work is still yours.
Related pages
Sources
Sources are the research digest for this comparison, last checked on 15 October 2026.
- WORX UK PowerShare (retrieved 15 October 2026)
- WORX UK cordless combi drills (retrieved 15 October 2026)
- WORX UK product warranty (retrieved 15 October 2026)
- Control of Vibration at Work Regulations 2005, regulation 4 (retrieved 15 October 2026)
- HSE CN3 drilling dust (retrieved 15 October 2026)
- GOV.UK electrical equipment safety regulations 2016 (retrieved 15 October 2026)
- GOV.UK faulty goods and refunds (retrieved 15 October 2026)
- amazon.co.uk WORX WX370.1 listing (retrieved 15 October 2026)