Cast Iron Kettlebells Explained: Weights And Colour Bands

We sell cast iron kettlebells singly in 12 weights: 4, 6, 8, 10 and 12kg, then 16, 20, 24, 28, 32, 36 and 40kg. Each bell has a coloured band on both sides of the handle, where it meets the bell, from mint green on the 4kg to brown on the 40kg, and its weight cast on the back in kg and lb. There's no 30kg bell: the nearest are 28kg (blue) and 32kg (grey).

We sell the kettlebells, racks and flooring in this guide. The product page doesn't yet list each bell's height, width or handle diameter, so the size section says what we can tell you instead.

What kettlebell weights do you sell?

Twelve weights from 4kg to 40kg, sold one bell at a time. They go up in 2kg steps from 4kg to 12kg, then in 4kg steps from 12kg to 40kg. Every bell is cast iron with a protective coated finish, made to a ±2% weight tolerance, and comes with a one-year warranty.

The colours are from the colour guide on the kettlebell product page, and the markings are as they appear on each bell in its product photos. The pound figures are the bells' own markings, so use the kg figure when you need the exact weight.

All twelve together weigh 236kg. On 9 October 2026 the 6kg, 10kg and 12kg bells were out of stock; the product cards below show today's stock.

Is there a 30kg kettlebell?

No, we don't sell a 30kg kettlebell. Above 24kg our range goes up in 4kg steps, 28kg, 32kg, 36kg and 40kg, so the nearest bells to 30kg are 28kg (blue band) and 32kg (grey band).

We do sell a 30kg slam ball, a sand-filled ball with no handle rather than a kettlebell. It was out of stock on 9 October 2026. Our conditioning kit guide explains what slam balls are.

What do the colour bands mean?

Each colour stands for one weight, so you can tell bells apart on a rack without reading them. Two pairs are easy to mix up: the 8kg and 28kg bells both have blue bands, and the 4kg is mint green while the 24kg is green. When it matters, read the weight cast on the back of the bell.

Kettlebell colour schemes aren't shared between makers. A band colour on another brand's bell, or in another gym, may mean a different weight from ours, so check the number rather than the colour when you add to a mixed collection.

How big is each kettlebell?

Each bell gets bigger as it gets heavier, but we don't publish exact sizes yet. Our bells are solid cast iron, so the weight comes from the amount of iron: a 40kg bell holds about ten times the iron of a 4kg one. The product page doesn't give each bell's height, base width or handle diameter. If you need one, ask us and we'll measure a bell from stock.

Three things help while those figures aren't published:

• Don't judge size from the photos. Each bell on the product page is photographed on its own and fills the frame, so the 4kg and the 40kg look the same size.
• Size decides how many fit on a shelf. That's why the storage section gives rack sizes but not a bell count. Tell us which weights you have and we can check.
• Competition kettlebells are a different design. They're usually steel and hollow, made to one outside size and handle at every weight, with the weight set by how much metal is inside. The bell stays the same size as you move up. We don't sell them: our range is cast iron only.

What finish do they have?

Cast iron with a protective coating, colour-coded by weight. The front of each bell carries the Equipped Gym logo, and the back carries the weight in kg and lb. The product photos show both sides of the same bell; each one you order is a single bell.

The one-year warranty covers manufacturing defects that affect a bell's structure, safe use or normal performance. It doesn't cover cosmetic wear from normal use, or damage from certain causes:

• Cosmetic wear: scratches and scuffs, paint or coating wear, minor dents, surface oxidation, fading or discolouration.
• Damage from: dropping bells onto unsuitable surfaces, throwing them, knocking them against racks, walls or metal equipment, outdoor or damp storage, and unsuitable chemicals or cleaning methods.

So keep them dry and indoors. If they live in a garage, deal with any damp first: our garage gym guide covers damp, cold and the garage door. The full terms are on our warranty page.

How do I store kettlebells?

On a kettlebell rack, or on the floor. We sell two 3-tier kettlebell racks, 111cm and 153cm long, both 103cm high and 57cm deep, in black powder-coated steel. They come empty, so you add your own bells, and both were out of stock on 9 October 2026.

• Tools. If you don't have 17mm tools, our 17mm spanner set is the minimum needed to assemble a rack.
• Room in front. The racks are 57cm deep. Leave space in front to lift a bell off the lower shelf.
• Set bells down. Knocking bells against the rack or each other isn't covered by the warranty.

What flooring goes under kettlebells?

Rubber tiles, chosen so that both the published use and the drop guide fit what you'll do. Our flooring page lists 10mm for light free weights and 20mm for free-weight areas. The heaviest bell we sell, 40kg, is under the drop guide figure for every thickness, from 80kg for 10mm. These are guide figures: the subfloor, drop height and how often weights are dropped all matter.

The drop guide only tells you a thickness can take the weight. The published use has to match your training too, and a collection that runs up to heavy bells is more than "light free weights". Our guide to gym flooring thickness explains how to read both. Remember that the kettlebell warranty doesn't cover bells dropped onto unsuitable surfaces.

Our rubber gym flooring tiles are 1 m × 1 m and are laid in a brick pattern, with each row offset by half a tile. If the room is upstairs or on a timber floor, read what you can lay rubber gym flooring on before you order.

Should I buy a pair or a range of weights?

That depends on how you'll train, which a qualified trainer can help you work out. What we can tell you is how buying works. Bells are sold singly, so a pair is two of one weight. The product page lets you choose several weights and add them to your basket together.

How much a selection weighs decides how it's delivered. These are examples, not recommendations:

Orders over 100kg come on a pallet, so you carry the bells in from the kerb yourself. Delivery is charged once per order by weight, from £7.99 up to 20kg to £59.99 for a pallet, and is free on UK mainland orders over £300.

What weight should I start with?

We can't tell you that from here. The right weight depends on you and the exercises you'll do, and a qualified trainer can help you find it. This guide sticks to the equipment. For how kettlebells compare with dumbbells and barbells, read free weights explained.

Other questions

Do you sell kettlebell sets?

No. We sell single bells only, so you choose the weights. The product page lets you add several weights to your basket in one go.

Can I keep kettlebells in a garage or outside?

Keep them indoors and dry. The warranty doesn't cover damage from outdoor or damp storage, or surface oxidation, so in a garage, deal with any damp before the bells move in.

How are kettlebells delivered?

Orders under 100kg come by parcel courier, and orders over 100kg on a pallet, unloaded at the kerbside. Orders placed before 8am on a working day are dispatched that day, and later orders the next working day. Parcels typically arrive the next working day after dispatch, and pallets in 2 working days, or around 5 working days to the Highlands, islands and Northern Ireland. These are courier estimates and can't be guaranteed. Full terms are on our delivery information page.

About this guide

This guide explains the cast iron kettlebells we sell, so it describes our own products. It is based on:

• the kettlebell, kettlebell rack and flooring product pages, and our warranty page, checked on 9 October 2026;
• the product photos of each bell, for the kg and lb markings;
• the questions customers send our team about kettlebell storage and stock.

The total weights are added up from the published bell weights. The note on competition kettlebells describes that type in general; we don't sell them. The guide doesn't give training advice: which weights and exercises suit you is a question for a qualified trainer.

Written by the Equipped Gym Team. Last reviewed 9 October 2026.