Different wooden backrests and armrests slot into the top of this aluminium chair by Japanese studio Nendo.
Designed for Italian furniture brand Alias, the Twig chair has five interchangeable tops that slot onto the same white metal base.
"Since the Italian furniture brand Alias specialises in furniture made from aluminium, the idea was to create a chair made of four aluminium 'twigs' and a seat," said Nendo, the Tokyo-based studio led by designer Oki Sato.
T-shaped elements, connected sections, and a high or low backrest were all shaped with curving edges to complete the chairs and provide "different seating experiences".
Dezeen Book of Interviews: Oki Sato features in our new book, which is on sale now
These wooden pieces slot into four stems that extend upward from the legs around the seat, which is available in wood and plastic, or upholstered with fabric.
"A number of different shapes and sitting experiences are achieved by fitting these units onto the four legs," said Nendo.
When the additions are removed, the seats can be stacked for storage and transportation.
Nendo – one of the most prolific design studios at the moment – has launched a variety of seat designs in the past year. The most recent examples include a chair with woodgrain patterns created using artificial suede, a stool that looks like it has missing supports and a minimal stacking office chair.
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An exhibition of over 100 Nendo products designed in the past year took place during Milan design week in April.
During an interview with Dezeen at the opening, Sato said that designing so many products at once "relaxes" him.
Photography is by Akihiro Yoshida.