Abstract: A chair has side units including support members 7, 8 articulated to arm rests 9, 10, respectively pivotally mounted at their distal ends to a horizontal rod 11 disposed below a seat 1 and to a back rest 3. The ends of the support members are bent at an angle of 70.degree. to 90.degree., and the units can be moved between raised and collapsed positions.

Abstract: The seat (1) and the back (2) are identically shaped shells (12) having side supporting ribs (10, 11). With the exception of the portion intended for connection to the other part, the supporting ribs are in the form of channels (13) open at the bottom. The remaining portion is in the form of a hollow cylinder (15) having a partition (17). The connecting members (3, 4) disposed on both sides consist of bent-over spring material (30) in band form. The ends (33, 34) of the arms (31, 32) of the connecting members are integrally fastened in slots (35, 36) in cylindrical pegs (37, 38) by means of screws (39, 40). The pegs (37, 38) are produced with snug fit tolerance in relation to the hollow cylinders (14, 15). An O-ring (40, 41) is compressed by means of a screw (44, 45) between the partition (16, 17) and the peg (37, 38). This provides adequate fastening of the connecting member even when thin-walled moulded polypropylene is used for the shells (12).