A conveyor is disclosed comprising a track having a pair of side rails and a plurality of interconnected carts which are reciprocally moveable along the track by a pneumatic cylinder. Since dependent on the security category different sensor parameters are made available for the respective checking of the security feature, so as to check the same security feature in different ways, the preparing of forgeries can be prevented particularly reliably. The steerable distal portion and the segment of the controllable portion are actuated by at least two tendons. A thin film transistor is formed by using the crystallized first silicon layer.