SDS max vs SDS plus: the shanks do not swap
Updated: 2026-10-23
SDS max vs SDS plus is a fit question. The two shanks do not interchange, and a 10 mm hole is not a 10 mm shank. If you own the smaller chuck, an SDS max bit will not enter it. An adapter faces from the larger chuck toward plus bits, not the other way. The five kept max bits are on the [SDS max drill bit comparison](/hub/drilling-and-accessories/sds-max-drill-bit). Diameter and length, once the shank is right, are on the [SDS max drill bit buying guide](/hub/drilling-and-accessories/sds-max-drill-bit/sub/sds-max-drill-bit-buying-guide).
SDS max vs SDS plus is a fit question. The two shanks do not interchange, and a 10 mm hole is not a 10 mm shank. If you own the smaller chuck, an SDS max bit will not enter it.
SDS max vs SDS plus is a fit question. The two shanks do not interchange, and a 10 mm hole is not a 10 mm shank. If you own the smaller chuck, an SDS max bit will not enter it. An adapter faces from the larger chuck toward plus bits, not the other way. The five kept max bits are on the SDS max drill bit comparison. Diameter and length, once the shank is right, are on the SDS max drill bit buying guide.
Our top picks
| Badge | Product | Shank | Diameter | Stated length | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Keewaki Keewaki 20 x 400 mm | SDS max, 18 mm. Not SDS plus. | 20 mm | Title 400 mm; one bullet 340 mm | 6.8 | about £17.99 | View offer |
| Best value |  UK Drills UK Drills 18 x 330 mm | SDS max, 18 mm. Not SDS plus. | 18 mm | 330 mm; working length not split | 5.6 | about £14.89 | View offer |
| Alternative |  UK Drills UK Drills 10 x 280 mm | SDS max, 18 mm. Not SDS plus. | 10 mm | 280 mm; working length not split | 5.6 | about £9.99 | View offer |
On this page
Two shanks, two chucks
Heller's shank page describes SDS plus as about 10 mm across, for hammers under about 5 kg, with two closed grooves and two wedge grooves. SDS max is about 18 mm, for hammers over about 5 kg, with two closed grooves and three wedge grooves. UK Drills, in a guide dated 23 September 2026, says the systems do not mix.
A plain SDS label usually means plus. Hilti uses TE-C for plus and TE-Y for max. Every bullet in this comparison says SDS max, about 18 mm. Filing the shank will not make it lock.
A 10 mm hole is not a 10 mm shank
UK Drills B01N410BGL is the worked example. The title is 10 × 280 mm, the price is £9.99, and the cutting diameter can match a 10 mm plug. The shank on the bullet is still about 18 mm and still SDS max. Someone with a domestic SDS plus drill, looking for a 10 mm plug hole, will order it because the 10 mm looks familiar. It will not enter that chuck.
If the drill is plus, buy an SDS plus bit of the diameter on the plug sheet. This max listing is the right family only when the housing says SDS max. The other four bits are 18 mm, 20 mm and 25 mm on the same 18 mm shank. Which of those holes to buy, once the chuck matches, is the best SDS max drill bit page.
Adapters face one way
UK shops sell adapters that face from the max hammer toward plus accessories. Hilti UK lists a TE-Y adapter, product 263359, at £127.20. Bosch Professional GB lists an SDS max to SDS plus adapter, part 1 618 598 159, at £46.72 including VAT. Neither puts an SDS max bit into an SDS plus drill. If your only hammer is plus, an adapter will not let you use B01N410BGL. Once the shank is right, seating and dust are on the how to use an SDS max drill bit page.
What the returns on these listings already say
The shared UK Drills reviews include returns because the shank would not fit a normal SDS or domestic drill. One review names a 12 mm × 400 mm advert. That text sits on all four UK Drills ASINs, so it is one pool. None of the five bullets says the bit fits SDS plus.
We used Heller's shank page, the UK Drills guide of 23 September 2026, the Hilti UK and Bosch Professional GB adapter pages, and the amazon.co.uk bullets. We did not run a lab test. A qualifying purchase through our links can earn a commission at no extra cost to you. Updated 22 October 2026.
Common questions
Will an SDS max bit fit an SDS plus drill?
No. The max shank is about 18 mm and the plus chuck is made for about 10 mm. Heller and the UK Drills guide both say the bits do not swap, and a max bit will not enter a plus chuck. Filing the shank does not create the plus grooves. Every listing in this comparison is SDS max.
Will an SDS plus bit fit an SDS max drill?
Not on its own. UK Drills says a plus bit will not go into a max chuck. Hilti's TE-Y adapter at £127.20, and Bosch's GB SDS max to SDS plus adapter at £46.72, are the products that let a max hammer take plus accessories. They are a separate purchase, and they face that one way.
Is SDS on its own the same as SDS plus?
On UK hammers, a plain SDS label usually means SDS plus, the shank of about 10 mm. SDS max is normally written as SDS max. Hilti uses TE-C for plus and TE-Y for max. The printed label wins when it disagrees with the weight of the machine.
Does a 10 mm SDS max bit fit a plus chuck?
No. B01N410BGL is 10 mm at the tip and about 18 mm at the shank, priced at £9.99. The 10 mm can be the right hole for a 10 mm plug. It is the wrong shank for an SDS plus drill. Buy a 10 mm SDS plus bit for that drill.
Is there an adapter, and which way does it face?
Yes, and only from a max tool to a plus bit in the UK pages we used. Hilti's TE-Y adapter is £127.20. Bosch Professional GB's SDS max to SDS plus adapter, part 1 618 598 159, is £46.72 including VAT. Pages that say nothing interchanges are describing a direct fit. Nothing in these sources puts a max bit into a plus chuck.
Why do reviews say the shank is too big?
Because the bit is SDS max, about 18 mm, and the drill was a normal SDS plus or a domestic chuck. That return text is in the shared UK Drills review pool, including one comment about a 12 mm × 400 mm advert, and the same text appears on all four UK Drills ASINs. It is not four separate tests.
Related pages
Sources
Public UK and manufacturer pages used for shank, dust, vibration and anchor-bit geometry, plus the amazon.co.uk listings for the five ASINs. Last checked on 22 October 2026.
- Heller Tools, Shanks (retrieved 22 October 2026)
- HSE CN3, Construction dust: drilling (retrieved 22 October 2026)
- HSE CIS36, Construction dust (retrieved 22 October 2026)
- HSE, Hand-arm vibration: assess the risks (retrieved 22 October 2026)
- HSE INDG175, Hand-arm vibration (retrieved 22 October 2026)
- HSE, Electrical systems on construction sites (retrieved 22 October 2026)
- Bosch Professional GB, PRO SDS max-7 drill bit (retrieved 22 October 2026)
- PGM, Check of standard drill bits (retrieved 22 October 2026)
- PGM, Marking of drill bits (retrieved 22 October 2026)