Abstract: The invention relates to a chair with adjustable seat depth, wherein the seat of the chair consists of a rigid seat support plate (1) and a sliding and ductile seat cushion plate (2), on which the seat cushion is arranged. The invention is characterized by the fact that the seat cushion plate (2) contains a flexible area (7), which forms a seat trough, that on the seat support plate (1) two lateral guide rails (8) are arranged, in which the seat cushion plate (2) can be displaced with guide ribs (6) that are incorporated in said plate and that between the seat support plate (1) and the seat cushion plate (2) a device (15) for improving the sliding characteristics, preferably a polyethylene foil that is coated with Teflon, is arranged. The chair is characterized by very good sitting comfort.

Abstract: A backrest, in particular for an office chair, is indicated, in which backrest a cover is stretched onto a frame. In order for it to be possible for the frame to be introduced into the cover in a simple manner, the frame is of hinged and rotatable design. The cover is stretched in the transverse and longitudinal direction by insertion of a transverse bow into the frame and fastening of the cover to the transverse bow.