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Head-to-head · Best Adjustable Kettlebells

Bells of Steel Adjustable Competition Kettlebell vs Bowflex SelectTech 840 Adjustable Kettlebell

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

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The short answer

Bowflex SelectTech 840 Adjustable Kettlebell comes out ahead by a clear margin (4.5 vs 4.2). The gap is mostly about Users prioritizing rapid weight changes during circuit training over durability — read the strengths below before deciding.

Bells of Steel Adjustable Competition Kettlebell
Ranked #3 in Best Adjustable Kettlebells
Bells of Steel Adjustable Competition Kettlebell
6 sources$179as of Oct 2

Built to Girevoy Sport Union standards, this kettlebell maintains a consistent shape and 35mm handle diameter that reviewers credit for proper balance during dynamic movements. Garage Gym Reviews found it durable enough to withstand drops without internal rattling, while Your Average Guy Style noted the manual plate adjustment is secure but time-consuming compared to dial systems. Lifehacker identified the 12kg minimum weight as a significant drawback for beginners or petite users who need lighter loads for strict overhead pressing. This unit fits advanced athletes seeking incremental progression in limited space, whereas novices should look elsewhere for lighter starting options.

Strengths
  • — Maintains a traditional competition kettlebell shape and dimensions, ensuring proper balance and comfortable movement during swings, snatches, and cleans.
  • — Offers highly incremental weight adjustments with included 0.5 kg and 1 kg plates, allowing for precise progressive overload within the base range.
  • — Constructed from durable steel and iron components that reviewers found stable and safe to drop without internal parts coming loose or rattling.
Watch-outs
  • — Weight adjustment is time-consuming as it requires manually unscrewing bolts and physically swapping iron plates rather than using a quick dial or pin mechanism.
  • — The minimum starting weight of 12 kg (approx. 26 lbs) may be too heavy for beginners, petite users, or those needing lighter loads for strict overhead pressing.
$179 · Buy at akfit.comFull review →
Bowflex SelectTech 840 Adjustable Kettlebell
Higher ratedRanked #1 in Best Adjustable Kettlebells
Bowflex SelectTech 840 Adjustable Kettlebell
5 sources$149as of Oct 2

The Bowflex SelectTech 840 consolidates six kettlebells into a single compact unit that maintains a consistent footprint regardless of weight selection. Shredded Dad found the dial adjustment system seamless, allowing rapid changes between sets with tactile confirmation for efficient circuit training. However, Men's Fitness noted the handle lacks an ergonomic groove for resting against the forearm during overhead presses or rack positions. The polycarbonate construction carries an explicit 'Do Not Drop' warning because impact can damage the internal locking mechanism, and CNET reported that JRNY app access is limited to tablets and smartphones without TV support.

Strengths
  • — Replaces six individual kettlebells (8 to 40 lbs) in a single compact unit, saving significant floor space.
  • — Features an easy-to-use dial adjustment system that allows for rapid weight changes between sets with a tactile click confirmation.
  • — Maintains a consistent overall shape and footprint regardless of the selected weight setting.
Watch-outs
  • — Constructed primarily from polycarbonate plastic rather than solid metal, carrying an explicit 'Do Not Drop' warning on the dial.
  • — The handle is welded to the base and lacks a sculpted ergonomic groove for resting against the forearm during overhead presses or rack positions.
  • — Weight increments are non-linear (8, 12, 20, 25, 35, 40 lbs), which may not suit users seeking consistent step-ups.
$149 · Check Price on AmazonFull review →

How they stack up

Bells of Steel Adjustable Competition Kettlebell

Unlike the Titan Adjustable Competition Style Kettlebell, which requires tools to adjust weight, this model allows for manual plate swapping without additional hardware, though both share a consistent competition-style shape. It offers finer 0.5 kg increments compared to the coarser cast iron plates of its sibling, but shares the same time-consuming adjustment process and lacks the quick-dial convenience found in the Bowflex SelectTech 840.

Bowflex SelectTech 840 Adjustable Kettlebell

This kettlebell features a rapid push-down and twist dial adjustment system, which is significantly faster than the manual plate loading required by both Bells of Steel and Titan models. However, its polycarbonate construction carries a 'Do Not Drop' warning, contrasting sharply with the durable steel or cast iron builds that reviewers found safe to drop for the other three products.

Specs side-by-side

SpecBells of Steel Adjustable Competition KettlebellBowflex SelectTech 840 Adjustable Kettlebell
Max Weight32 kg (70.5 lbs) with expansion40 lbs (18.14 kg)
Handle Diameter35 mm (1.4 in)—
MaterialSteelPolycarbonate shell with steel plates
Weight Range12-20.5 KG8-40 lbs
Weight Increments0.5kg6 settings (8, 12, 20, 25, 35, 40 lbs)
Adjustment MechanismInternal locking systemPush-down and twist dial
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