Microprocessor electronics feature speed preselection, speed stabilization via a tachogenerator, soft start, and restart interlock after power failure. It includes overload protection and temperature monitoring. The unique tool attachment with quick coupling allows for tool-free changes of system attachments for satin finishing and pipe belt grinding. The fully potted electronics module prevents damage from dust. The three-fold winding protection reduces motor wear and extends service life. Abrasive belt change is fast and tool-free, with a sanding belt dimension of 760 x 40 mm. The high-quality, spring-mounted sanding arm is made of lightweight metal and includes two deflection rollers for optimal wrapping of pipes up to a maximum of 270 degrees. It also features a single-pole switch and spindle lock.