By Jack Atkins, Home Gym Equipment Specialist · Updated 8 November 2026
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The PowerBlock KettleBlock is a well-built adjustable kettlebell that swaps between seven weights from 8lb to 40lb (about 3.6kg to 18kg) in a few seconds, and it's a decent answer for anyone with almost no floor space. It's also £297 at the time of writing, which is a lot of money for a bell that maxes out at 18kg, uses pounds rather than kilos, and doesn't feel like a cast kettlebell once you get into cleans and presses. We rate it 3.7 out of 5: good hardware, poor value.
That price is the heart of this review. PowerBlock's dumbbells, like the PowerBlock Elite EXP, earn their premium by replacing a rack of dumbbells worth far more. The KettleBlock covers a range where cast-iron bells are cheap, so the maths that makes PowerBlock dumbbells good value doesn't carry over.
How we review
We haven't had a KettleBlock in for hands-on testing. This review is built from the manufacturer's specifications, the Amazon UK listing, PowerBlock's published product information and recurring themes in verified owner feedback. Where owners disagree, we say so, and we only report prices from the listing at the time of writing.
Most kettlebells are a single lump of cast iron. The KettleBlock takes PowerBlock's selector-dumbbell idea and applies it to one handle: a steel frame and handle sit inside a nested stack of square, colour-coded plates, and you choose how many plates come up with the handle. Lift it out and you're holding the weight you picked; set it back down to change it.
The Amazon listing gives the 40lb version's settings as 8, 12, 20, 25, 30, 35 and 40lb, and PowerBlock pitches it as replacing eight kettlebells, or 186lb of fixed bells. The whole unit measures 11 by 11 by 16 inches (roughly 28 by 28 by 41cm), so it takes up about the footprint of a single large cast bell. Warranty on the listing is three years on parts and five years on the weights.
It's worth knowing that this is the older KettleBlock design. PowerBlock's adjustable kettlebell page now lists newer Sport and Pro models in 10 to 20lb, 18 to 35lb and 35 to 62lb ranges, and doesn't show the 8 to 40lb KettleBlock at all. The Amazon UK listing was down to five units when we checked, so stock may not last.
| Weight range | 8 to 40 lb (approx 3.6 to 18.1 kg) |
|---|---|
| Settings | 8, 12, 20, 25, 30, 35, 40 lb |
| Settings in kg (approx) | 3.6, 5.4, 9.1, 11.3, 13.6, 15.9, 18.1 kg |
| Replaces | 8 kettlebells / 186 lb of fixed bells (manufacturer claim) |
| Dimensions | 11 x 11 x 16 in (approx 28 x 28 x 41 cm) |
| Listed unit weight | 42 lb |
| Shape | Square block with top handle |
| Warranty | 3 years parts, 5 years weights |
| Price | £297.00 at the time of writing |
A round cast bell has its centre of mass hanging below the handle in a predictable arc, and that shape is what lets it roll over your wrist and settle against your forearm in the rack position. The KettleBlock is a square box. For two-handed swings, deadlifts and goblet squats that barely matters, because you're holding the handle and the load hangs underneath it much as a normal bell would. Owners generally report that these lifts feel fine.
Cleans, snatches and single-arm presses are a different story. The flat sides and corners rest on the forearm differently from a curved bell, and some owners find the edges dig in or the block sits further from the body than they're used to. If your training leans on the rack position, and most kettlebell programmes do once you get past the basics, you'll notice it every session. Experienced kettlebell users tend to be the harshest critics here, which makes sense: they know what a bell should feel like.
The handle is also part of a frame that has to lift plates cleanly every time, so it doesn't have the thick, smooth, single-piece feel of a good cast bell. It does the job, but it isn't the reason you'd buy this.
Every plate on the KettleBlock is marked in pounds. That's a nuisance rather than a dealbreaker, but UK programmes and coaching cues are almost always written in kilos (8kg, 12kg, 16kg, 24kg), so you'll be converting, and the KettleBlock's settings don't line up neatly with standard bell weights. Its 35lb setting is about 15.9kg, close enough to a 16kg bell; the top 40lb setting is about 18kg, which falls between the common 16kg and 20kg jumps.
The bigger issue is the ceiling. Our kettlebell weight guide puts beginner men at 12 to 16kg for two-handed swings and intermediate men at 20 to 28kg, so an 18kg ceiling doesn't leave much headroom once you're past the beginner stage. Intermediate women (16 to 20kg in the same chart) will hit the top setting before long too. Lake and Lauder's six-week study on kettlebell swing training used 12kg for lighter participants and 16kg for those over 70kg, and found strength and jump-height gains similar to jump-squat power training. So a 3.6 to 18kg bell covers genuinely useful swing loads; it just won't take a stronger lifter much further. PowerBlock did sell a conversion kit for the older model that pushed it to 25kg (55lb), but we couldn't find one on sale in the UK.
At the light end, the jump from 12lb (5.4kg) to 20lb (9.1kg) is a 3.7kg leap in one step. For goblet squats that's manageable, but for overhead presses and Turkish get-ups it's a big ask for a beginner, and those are exactly the people the 8lb starting weight is meant to suit.
Here's where the KettleBlock struggles. In our adjustable kettlebell guide we priced a starter trio of 8kg, 12kg and 16kg cast-iron bells at roughly £80 to £120, which covers most of what the KettleBlock does for well under half the money. Even adding a 20kg bell keeps a fixed set comfortably cheaper, and you'd get proper round bells in kilo weights.
Among adjustables, the BowFlex SelectTech 840 covers almost the same 3.5 to 18kg range with a dial, and was around £199 when we priced it for that guide. If you're spending close to £300 anyway, the Bells of Steel adjustable kettlebell runs from 12kg to 32kg in 0.5kg steps with a proper competition shell, so it keeps going long after the KettleBlock runs out. The trade-off is that Bells of Steel needs tools and about a minute to change the weight, and it can't go lighter than 12kg.
So the KettleBlock's case rests on two things: fast changes and a small footprint at the light end of the range. If you want to move from a 5kg halo to an 18kg swing within one circuit, and you genuinely can't fit four bells in your space, it does that well. That's a narrow use case for the money.
Kettlebell or dumbbell?
If you're torn between a kettlebell and adjustable dumbbells for a small space, our kettlebell vs dumbbell guide runs through which lifts suit each. Some PowerBlock dumbbell sets accept a separate kettlebell handle, which can be better value if you'd buy the dumbbells anyway.
Kettlebell training itself has a reasonable evidence base for strength and pain outcomes in everyday adults. A randomised trial by Jay and colleagues found that eight weeks of ballistic kettlebell training cut neck, shoulder and low back pain in workers from high-pain occupations and improved low back strength, though aerobic fitness didn't change. A wider scoping review of kettlebell training in clinical practice was more cautious, concluding that most studies were small and effects were typically trivial to small.
None of that research is about the KettleBlock specifically, and the loads involved (mostly in the 8kg to 16kg band) sit comfortably within its range. The point is that you don't need anything clever to get the benefits of swings, cleans and goblet squats; you need a bell of the right weight and the consistency to use it. Our kettlebell swing guide covers the technique.
If you do buy one, the settings map fairly well onto a simple full-body kettlebell session. Most adults could use the 30 to 40lb settings (13.6 to 18kg) for two-handed swings and goblet squats, drop to 20 or 25lb (9 to 11kg) for single-arm rows and presses, and use 8 or 12lb (3.6 to 5.4kg) for halos and warm-up drills. Because each change only takes a few seconds, you can run those as a circuit without a pile of bells around your feet, which is the one job the KettleBlock does better than a fixed set.
What you can't do is progress in small steps at the top. Once 40lb swings feel easy, there's nowhere to go except more reps, longer sets or harder variations such as single-arm swings, and that point arrives sooner than most buyers expect.
Buy the KettleBlock if floor space is your hard limit, you train mostly with swings, deadlifts, goblet squats and rows, you want quick weight changes inside a workout, and you're happy working in pounds. It also suits households where a lighter user and a moderately strong user share one bell, as long as the stronger person doesn't need more than 18kg.
Skip it if you train cleans, snatches and presses regularly, if you want room to progress past 18kg, or if £297 matters to you. A couple of cast-iron bells from our best kettlebells UK guide will feel better in the hand for a fraction of the cost.
See today's price on the PowerBlock KettleBlock£297.00 at the time of writingThe 40lb KettleBlock adjusts from 8lb to 40lb, which is roughly 3.6kg to 18.1kg. The listed settings are 8, 12, 20, 25, 30, 35 and 40lb. There's no setting between 12lb and 20lb, which is an awkward jump for beginners doing presses.
Pounds. PowerBlock is an American company and the KettleBlock is marked in lb only. 40lb works out at about 18kg, so the heaviest setting sits between a standard 16kg and 20kg bell. You'll need to convert if you follow UK programmes written in kilos.
Not quite. It's a square block with a handle on top rather than a round cast bell, so it rests differently on your forearm in cleans, presses and snatches. Swings and goblet squats feel close enough to a normal bell; the rack position is where most owners notice the difference.
For most people, no. At £297 at the time of writing it costs more than a full set of cast-iron bells covering the same range, and more than dial-adjust rivals with a similar 18kg ceiling. It makes sense if floor space is the real constraint and you want fast weight changes in one compact unit.
No. PowerBlock's own site now lists Sport and Pro adjustable kettlebells in 10 to 20lb, 18 to 35lb and 35 to 62lb ranges. The 8 to 40lb KettleBlock is the older design, which is still sold on Amazon UK in limited stock.
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