I'm just an opportunity drills, but the thing is super! A small drawback, if you attaches the machine, and andrückst, slams the 16 A fuse! So start pressure and see what happens! The device has a significant impact and eats into my reinforced concrete as in warm butter! Have only 32 holes drilled, the thing has been done at the price already paid for! I live in such a concrete bunker from 1968! Reinforced concrete at its best, all my old Maschienen have failed here !!! I recommend the device!