About A Chair AAC 24 office chair by Hee Welling

HAY writes that "the full-bodied, rounded shell and unified silhouette of the AAC 24 add executive weight and bring a warm, welcoming expression to an otherwise functional and technical genre, that of the office chair." The brand considers it "particularly suitable for formal or official contexts, and home offices."

The shell: recycled polypropylene, what HAY calls "2.0"

The seat and backrest form a single injection-molded shell made from post-consumer plastic waste: this is what the "2.0" in the color names refers to. The material is dyed throughout: a scratch will not reveal a different color underneath, and maintenance is limited to soapy water. On lighter shades, slight variations in tone are inherent to recycled material.

Castors, but no gas lift: the distinction to know

The base is a four-star aluminum star, mounted on castors, on which the shell swivels. This is what HAY calls a four-star castor base.

This model does not have a height-adjustment gas lift. The seat height is fixed. This is what separates it from the About A Chair 50, 52, and 252, whose five-star base features a pneumatic gas lift. We mention this because nothing in a photo allows you to see it, and because it is the primary criterion for a workstation: to adjust the height to a desk, you need a gas lift; to roll from one point to another around a table, castors are sufficient.

Three base finishes: polished aluminum, black powder-coated, or white powder-coated.