Stealth Adjustable Kettlebell Review

The Stealth Adjustable Kettlebell is made by the same Assassin Goods behind the Stealth dumbbells. It comes in two models - the Stealth 16 (8-16kg, red) and Stealth 24 (16-24kg, blue) - both adjusting in 2kg increments via removable internal plates.

The standout feature is the cast iron construction. Where most adjustable kettlebells feel like hollow shells with weights rattling around inside, the Stealth feels like a proper kettlebell. Users consistently describe it as "solid, no rattling, and very close to a traditional kettlebell."

Our recommendation:

• New to kettlebells: The Stealth 16 (8-16kg) at £99. Most beginners will use 8-12kg for swings and 8-10kg for presses. The 16kg ceiling gives you room to progress.
• Intermediate: The Stealth 24 (16-24kg) at £119. If you already swing 16kg comfortably, this gives you progression to 24kg.
• Best value: The bundle (both models) at £225. This saves £93 vs buying separately (£99 + £119 = £218, so the saving is actually vs the original prices of £155 + £190 = £345). Covers the full 8-24kg range in 2kg steps.

Each Stealth kettlebell ships with 4 x 2kg inner weight plates. To change weight, you:

1. Place the kettlebell upside down
2. Remove the base plate
3. Add or remove 2kg plates
4. Replace and secure the base plate

This is slower than dial-select systems like the Bowflex 840, where you twist a dial and go. Expect 15-30 seconds per weight change. It's not ideal for circuits where you switch weight every set, but it's fine if you use the same weight for most of your session.

The upside of the plate system is simplicity and security. There are no mechanisms to jam, no dials to break, and the plates lock in with no play or rattle. When it's loaded, it behaves exactly like a fixed kettlebell.

Cast iron throughout. This is the single biggest differentiator. The Bowflex 840 uses a plastic housing. The Mirafit uses a plastic shell with internal weights. The Stealth is solid cast iron with a flattened base for floor stability.

Dimensions are 18cm diameter x 26cm height - compact enough for any home setup. The handle is comfortable for swings and presses, though Assassin Goods don't publish the exact handle diameter.

One thing to note: the warranty is only 1 year, which is shorter than the 24-month warranty on the Stealth dumbbells. For a cast iron product this is less of a concern (there's very little that can go wrong), but it's worth knowing.

The biggest limitation is that no single Stealth kettlebell covers the full 8-24kg range. The Stealth 16 goes 8-16kg and the Stealth 24 goes 16-24kg. If you want the full range, you need both (or the bundle).

This is a physical constraint of cast iron adjustable kettlebells - the shell size has to match the weight range. A shell big enough for 24kg would be too large and unwieldy at 8kg. The split design keeps each unit feeling like a properly sized kettlebell at every weight setting.

Compare this to the Bowflex 840, which covers 3.5-18kg in a single unit - but does so with a plastic housing that feels nothing like a real kettlebell.

Prices checked April 2026. Bowflex 840 UK price varies by retailer.

The Stealth and REP Fitness are the most similar - both cast iron, both plate removal, both feel like traditional kettlebells. The REP is available through uk.repfitness.com and Amazon UK but pricing fluctuates. The Mirafit is a solid middle ground with faster weight changes but a less authentic feel. The Bowflex is the fastest to adjust but feels the least like a real kettlebell.

Trustpilot reviews for Assassin Goods include a small number of kettlebell-specific mentions:

• "Really well built - solid, no rattling, and feels very close to a traditional kettlebell. The handle is comfortable and secure, even during longer sessions."
• "I must of researched every adjustable kettlebell you can buy, these are by far the best, they are cast iron, the right size, solid weight changing mechanism, 100% recommend."
• "Usable straight out of the box and super solid."

As with the Stealth dumbbells, independent reviews outside Trustpilot are limited. There are no YouTube reviews or Reddit discussions specifically about the Stealth kettlebell that we could find.

Great for

• Home gym users who want kettlebell training without buying 5+ individual bells
• Anyone who values a traditional cast iron feel over convenience
• Beginners to intermediate lifters working in the 8-24kg range
• People who use the same weight for most of their session
• Stealth dumbbell owners who already trust the brand

Not for

• Circuit training with frequent weight changes (too slow)
• Advanced lifters who swing 24kg+ regularly
• Anyone who wants a single unit covering the full range
• People who need the fastest possible weight changes (get the Bowflex 840)

A well-built cast iron adjustable kettlebell that genuinely feels like the real thing. The 2kg increments and solid locking system set it apart from plastic-feeling competitors. The main limitation is the split range - you need both models (or the bundle) to cover 8-24kg. Best for home gym users who want kettlebell training without a full rack.