Marian Sigmund, an architect and designer, founder of the pre-war Ład Art Cooperative, starts working in Bentwood Furniture Factory. In Jasienica he is responsible for the development of new models of chairs and armchairs for export. Several models designed by him are produced, including the chair labeled as A-5870, put into production in 1958. Made of bent beech wood and plywood, combining two colors, with cut and bowed legs, the chair stands out against others. For example, it becomes extremely popular in UK schools. Now, its production is resumed in limited edition under the name SIG 1.