Microprocessor electronics: Speed preselection, constant speed control with tachogenerator, soft start, and restart interlock after power failure. Overload protection and temperature monitoring. Unique tool attachment with quick-release coupling for tool-free change of system attachments for satin finishing. Tube belt grinding and file attachment. Satin finishing adjustable, enabling work close to the edge with narrow rollers, including rip fence. Tool-free grinding tool change via patented quick-change system. Completely encapsulated electronic component prevents damage from dust. The three-fold winding protection reduces motor wear and extends service life. Adjustable protective cover for grinding tools up to 125 mm. Single-pole switch and spindle lock for optimum processing of various materials for satin finishing, structure, polishing, brushes, smoothing, derusting, and deburring of steel and stainless steel surfaces.