The bold, self-assured lines of this iconic sofa by Mario Bellini bear witness to the unlimited creative verve of the 1970s. During that same decade, Bellini devised the Libro dell’Arredamento, which launched a contemporary lexicon of design keyed on the primary function of the furniture illustrated. One outcome was a major experimental initiative conducted in association with the Cassina company’s Research Unit that led to the creation of Duc. This highly original and far-reaching design was based on the application of innovative materials to structural technology. The Duc sofa is composed of steel-framed panels in a state-of-the-art high- density polyurethane foam that are hooked on to the base and are then zipped together, top to bottom, on each side. The collection includes an armchair, as well as two-and three-seater sofas, all of them very sophisticated and extremely comfortable.