A protection or shading system for a motor vehicle, in particular a wind deflector system for a convertible, with a base, a sheet-like structure entendable between an inoperative position and a functional position in an extension direction away from the base, a rigid end element fastened to the sheet-like structure, and an extension device fastened on one side to the base and on the other side to the end element. The extension device is designed so as to transfer the system from an inoperative state in which the sheet-like structure, the end element and the extension device are each in an inoperative position, into a functional state, in which the sheet-like structure, the end element and the extension device are each in a functional position.