Seat adjusting device and method of providing seat adjustment

A seat adjusting device comprises a plurality of inflatable chambers (2-5) and a valve module (10). The plurality of inflatable chambers (2-5) includes a first inflatable chamber (2) and a second inflatable chamber (4). The valve module (10) comprises a control valve (11) which is a 4/4-way valve having four ports (41-44) and four positions. A first port of the control valve (11) is in communication with the first inflatable chamber (2) and a second port of the control valve (11) is in communication with the second inflatable chamber (4).