About A Chair AAC 11 swivel chair by Hee Welling

HAY summarizes the AAC 11 in one sentence: "with its swivel base and upholstered seat, the About A Chair AAC 11 combines functionality, formal expression, and comfort." Same dimensions and same base as the AAC 10, with the shell fully upholstered.

The upholstered shell, and what the textiles are

The shell is the same as the non-upholstered models, molded recycled polypropylene, according to the HAY product sheet, but here it is fully upholstered. Foam is placed over the shell and then covered with the chosen upholstery: the feel is softer and sound is better dampened in high-traffic rooms. Conversely, upholstery must be cleaned by dabbing rather than spraying.

The upholstery options offered here: Hallingdal 65, Kvadrat wool (70% wool, 30% viscose), the company's classic, very durable; Sense, HAY's aniline leather, dyed through: it shows the grain and develops a patina with use; Sierra, Ca-Mo corrected-grain leather with a pigmented finish, uniform and easy to live with; Bolgheri, HAY fabric with a rich blend (viscose, wool, polyamide, silk, linen); Remix 3, Kvadrat melange wool (92% wool, 8% nylon); Linara, Romo cotton-linen fabric (63% / 37%) with a matte look; Turf, HAY blended fabric (polyester, wool, acrylic, cotton).

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

The base is a piece of cast aluminum—as HAY writes, cast aluminium swivel base—with four legs spreading from a single center. The shell swivels on this base. The glides are standard glides, not casters: the chair rotates on itself but does not move on its own, which is more suitable for a meeting or dining table than for a workstation.

Two finishes. Polished aluminum is bare, shiny metal, whose luster comes from mechanical polishing: it shows fingerprints slightly and can be revived with a soft cloth. Black powder-coated aluminum receives a kiln-fired powder coating: a thick, matte layer that is more resistant to impacts. HAY presents this base as having "a more formal expression" than the models with wooden legs.