Seat with adjustable profile and module support

The seat has a backrest and gas or air-inflatable cushions (5a, 5b, 5c) on a common flexible modular support unit (M). The cushions are connected to a source of compressed air through a line provided with a controllable valve (10) that communicates with a control unit for air through a control line. A pressure sensor is provided for each cushion where additional components are integrated in the support unit.