About A Chair AAC 220 swivel chair by Hee Welling

HAY describes the AAC 220 as having "a swivel base in aluminium" and "a slightly higher backrest", with "a deep, generous seat". As with the AAC 212, 222 and 226, the armrests are low: they support the forearm and allow the chair to slide under a table or desk.

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

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

The swivel base: cast aluminium, polished or powder-coated

The base is a piece of cast aluminium: HAY writes cast aluminium swivel base: the four legs of which spread out from a single centre. The shell swivels on this base. The gliders are standard gliders, not castors: the chair rotates on itself but does not move on its own, which is more suitable for a meeting or dining table than a workstation.

Two finishes. The polished aluminium is a bare, shiny metal whose lustre comes from mechanical polishing: it shows fingerprints slightly and can be revived with a soft cloth. The black powder-coated aluminium has a kiln-baked powder finish: a thick, matt layer that is more resistant to knocks. HAY presents this base as "a more formal expression" than that of the wooden-legged models.