Adjustable Kettlebells: Check the Settings Before You Buy

An adjustable kettlebell solves a storage problem, but it creates a different programming question: will its available settings work for the movements you actually do? The BowFlex SelectTech 840 offers six settings between 8 and 40 pounds. This desk assessment uses its published specifications and manual. We have not tested a unit, measured its durability or established how often its mechanism fails. The useful comparison is with the few fixed bells a household needs, rather than an imaginary purchase of every weight available.

Map the settings to your movements before buying

Make a short list of intended exercises and the load currently usable with controlled technique. Compare that list with the six settings, paying particular attention to gaps rather than the maximum. As an illustrative purchase check, someone who needs a small increase for an overhead press may find the jump between settings less useful than someone buying mainly for loaded carries. Neither person needs six separate fixed bells by default. Also measure the storage location with the base included and allow room to lift vertically out of it. These are fit checks for a purchase, not a tested training prescription.

What the dial buys you

Turn the selection dial at the top of the handle and the mechanism locks only the plates needed for your chosen weight. The 840's six settings are 8, 12, 20, 25, 35, and 40 pounds. That progression is sensible for goblet squats, lunges, rows, presses, and moderate swings, and it lets several people in one household share a single bell at different loads.

The manufacturer lists a footprint of 8.8 by 7 by 12.5 inches and six settings: 8, 12, 20, 25, 35 and 40 pounds. That is a clear storage advantage over six separate bells, but a smaller fixed-bell purchase may fit some households just as well.

Programming around six settings is easier than it sounds. A sensible week pairs heavier goblet squats and two-handed swings at 35 or 40 pounds with presses and rows at 20 to 25, plus core work such as halos and suitcase carries wherever the dial lands. The jumps between settings are large — 12 to 20 to 25 pounds — so beginners sometimes hold two positions in one session rather than chasing perfect increments, and that is fine: the load that lets you finish every rep with two clean ones in reserve is the right load, whatever the dial says. As strength climbs, the 40-pound ceiling becomes the natural graduation point to a heavier fixed bell rather than a reason to abandon the format.

Compare the current delivered price of the adjustable bell with a basket of fixed bells in the weights actually needed. The answer changes with local suppliers, shipping and second-hand availability. Buying six bells is unnecessary for someone who would only use two, so a complete-rack comparison can overstate the saving.

The shape problem every adjustable has

A cast-iron kettlebell is a sphere with a compact center of mass, and much of kettlebell technique — the float of a good swing, the rack of a clean, the settle of a press — depends on that geometry. An adjustable kettlebell is unavoidably boxier. The plates live inside a wider housing, the load sits differently, and the shell does not sit on the forearm the way iron does.

The adjustable housing differs from a traditional fixed bell. Shape and clearance are worth checking for the intended movement, but this desk review cannot establish that every swing or press feels equivalent. Advanced ballistic practice requires suitable equipment and technique; a published maximum weight is not validation of every movement style.

Handle feel and grip

The dial is adjusted while the bell is seated in its base, following the manual. Decide whether that process fits the intended session rather than assuming a fixed change time. Do not improvise an adjustment while holding the load.

A session that alternates loads requires returning the bell to its base for adjustments. Compare that workflow with keeping two fixed bells available; neither the time needed nor the cost advantage has been measured for this article.

Safety, durability, and the 40-pound ceiling

The selection mechanism makes the manual essential reading. Check the assembly and locking procedure specified for the exact model, and do not use a damaged or insecure unit. We do not have verified sales totals or a denominator for mechanism failures, so this article cannot estimate a failure rate or promise that ordinary use eliminates mechanical risk. The design is not intended for dropping or slams.

The 40-pound ceiling is a purchase constraint, not a prediction about how quickly someone will progress. Compare the maximum and the intermediate settings with present needs. A household already using heavier loads should consider a different range rather than assuming this model will be sufficient.

Verdict: who should buy one

Store the bell in its base and follow the adjustment procedure in the manual. If plates do not seat or lock as instructed, stop using it and contact product support. An inspection is a maintenance step, not proof that an adjustable mechanism cannot fail. We have not performed durability or drop testing.

An adjustable kettlebell makes sense if space or budget rules out a rack of iron, if your programming centers on squats, presses, rows, carries, and moderate swings, and if you value progression within one piece of equipment. The SelectTech 840 is the polished, widely reviewed expression of that idea: six verified settings, a comfortable consistent handle, and a price that undercuts nearly any multi-bell purchase.

Buy fixed iron instead if you train mostly heavy ballistics, compete in kettlebell sport, or drop your equipment on purpose. For everyone else, the space-saving trade-off is real but smaller than the price and footprint savings it buys.