A main-frame bar and/or to a wing-frame bar for a main frame and/or a wing frame of a window, of a door, or of a façade element includes a main profiled element having a substantially U-shaped cross-section in single- or multi-piece design, which has, as viewed in a cross-section, a short leg, a long leg, and a transverse leg formed therebetween. A free intermediate space is formed between the ends of the short leg and of the long leg facing away from the transverse leg, a cover element and/or a fitting part extending over the intermediate space at least in some sections. The short leg and the long leg of the main profiled element have multi-function contours on the inner sides thereof facing each other, which multi-function contours completely or partially bound at least the following groove: in each case, a fastening groove open in the same direction on the side facing away from the transverse leg for fastening a corresponding fastening means of the fitting part or of the cover element.