49 solid wood blocks, each one individually spring-suspended inside the outer wooden cube. The springs work separately, so the blocks under the weight travel and the blocks at the edges stay put, and the seat keeps changing shape as the sitter moves.

200 kg, which is 441 lb. That is a high rating for a 45 cm stool and it matches the figure on the Coreformer and the VivaBall. The stool's own weight is 18 kg (40 lb).

45 x 45 x 45 cm. It is a true cube, so the seat height and the floor footprint are the same number, which makes it straightforward to line up with a desk, a bench or another HedgeHock. Nothing overhangs the base, so several of them push together without a gap.

One year from first shipment, extended to two years on components and two years on wooden components by registering the product within the first year of purchase. Spare parts carry ninety days, and the cover applies to private and commercial use alike.

No. It ships as one package and is used straight out of the box, with the casters already fitted. There is nothing to tension, adjust or maintain on the block mechanism.

The four casters are rubberised. An 18 kg stool rolls between a desk and a seating group with a push of the foot, and the rubber keeps the floor underneath it intact. On carpet the casters still roll, though a 45 cm cube is light enough to lift if you would rather.

It is the name for sitting on a seat that moves with you and never holds one fixed shape. On the HedgeHock the movement comes from 49 independently sprung blocks, each travelling a different amount as your weight shifts. It is a description of how the seat behaves, and how much anyone uses it that way is up to them.

All six of the NOHrD woods, with Shadow the least expensive and Walnut the most. A block grid puts 49 separate faces and a great deal of end grain in front of you, so the wood choice makes more visible difference on this stool than it does on a frame or a panel. The 49 blocks are solid through, so what you are choosing is the wood itself and not a face laid over something else.

It is a 45 cm cube rated to 200 kg with four casters underneath, so treat it as a seat first. If you want a step platform with a locked base and a published step-up height, the StepBox and the StepTower are the pieces built for that, both with a 30 cm step-up height.

Both are rated to 200 kg and both are bought as seats that move. The HedgeHock is 18 kg of solid wood on casters and looks like furniture; the VivaBall is a 75 cm ball weighing 1 kg in a washable cotton cover, and it rolls away when nobody is sitting on it. The HedgeHock needs no assembly, the VivaBall does.