Siege of motor vehicle

A seat (1) for a motor vehicle, comprising: - a supporting structure (10), - at least one connecting rod (41) which, on one side, is hinged to said bearing structure (10), and that on the other side, is hinged to a frame part (100) of the motor vehicle, and - locking means (50) the position of said movable mounting means, which include at least one fastener (51) adapted to cling to an attachment member (151) provided on said frame part of the motor vehicle.