An innovative take on the kettlebell, the flexible Fluikettle adds a little instability to make workouts more challenging…

If you’re looking for a stable, reliable workout from one of the best kettlebells, the Reax Fluikettle fluid-filled kettlebell won’t be for you. This innovative take on the kettlebell is deliberately designed to make the load – and your exercises – more unpredictable. So your workouts are more challenging for mind and muscles. 

Men’s Fitness verdict

The Fluikettle is a novel take on the kettlebell that can not only stand any impact but creates an unpredictable load to work your muscles in different ways. It takes some getting used to, though.
  • Shock and impact absorbing
  • Good for outdoor use
  • Comfortable against the skin
  • Not the most comfortable grip
  • Shifting weight takes some getting used to

How we tested the best kettlebells

Our testers Kieran Alger and Leon Poultney are experienced product reviewers of all manner of fitness kit. They tested these kettlebells at various weights and through a range of exercises at high rep ranges to see how they handle. They marked each one for grip, comfort (and weight range for the adjustable options) and gave an overall score that takes build quality, performance and price into consideration.

Reax Fluikettle features

This is the only kettlebell with a mix of fluid and steel balls inside that move with you during every drill. The constantly shifting weight of the water and those balls creates an unpredictable load that keeps you on your toes, and tests your strength, balance and movement in ways other predictable kettlebells can’t.

It’s an easy way to enhance any strength workout and it certainly makes things more interesting. It’s particularly good if you want to incorporate throws and catches into your regime. 

Reax Fluikettle weight range

The Reax Fluikettle range features nine weights from 2kg to 20kg in 2kg increments (though there’s no 18kg). They also have a soft, flexible outer that soaks up shocks and protects floors and limbs from any impact. The slightly squishy sensation also means they rest comfortable against your arms during drills. 

Unlike regular kettlebells, the Fluikettle can also be thrown, lifted and slammed to the ground – from as high as 10m – and it’s much more suitable for outdoor training. The slightly angular grip isn’t the comfiest and takes a bit of getting used to. 

They’re also slightly bulkier than standard bells so you’ll need to take storage space into consideration. Fortunately, stubbing your toe on one of these is a much less painful experience than bashing it into a brutal cast-iron bell. 


Weight range:4.4lbs to 44lbs / 2kg to 20kg
Number of weights:9
Features:Soft Shock elastic exterior, steel ball and fluid interior