A processing element for processing a profile-shaped or flat metallic workpiece, with the processing element designed such that a plurality of similar processing elements can be arranged one behind the other on a supporting device in the longitudinal direction of the supporting device, the supporting device can be driven in a circulating manner and the plurality of processing elements can be guided past the workpiece for surface processing at least approximately linearly by means of the supporting device. A rectangular or block-shaped main body having bearing surfaces for bearing on the supporting device is provided, and oblong ribs protruding outward in a web-like manner are provided on the main body on opposite flat longitudinal sides and overlap the corresponding opposite flat longitudinal sides of the main body on an identically embodied processing element, which is arranged between the ribs.