Have bought equipment for installations in new apartment. 6mm holes for anchors in concrete creates the machine just yet. When the fun is over 8mm. The thing is overheated and hardly brings up no Schlagbohrleistung. According to operating instructions should be possible even 14mm - I can not imagine. Had me according to the reviews on Amazon clearly expected more. So rather stay away, unless you just want a little tickle the wall / ceiling. Pity!