The wrapper (1) has a wrapping table (5) mounted on a basic frame (16). A winding arm (6) is arranged at a rotary bearing (10) above harvested crop bales (4). The winding arm holds film rollers (7), and is displaced in a vertical spacing (h) relative to the wrapping table for adjustment to different bale sizes. A control device causes displacement of the winding arm depending on parameters e.g. bale diameters, determined by sensors. The control device is automatically displaced to the winding arm in the vertical spacing to the wrapping table in course of a wrapping operation of the crop bales.
