... applied to drilling holes horizontally or with inclination on rocks with middle and high hardness (f=8 ... control,mechanism,quick,to,start,up,with”air-on,water-on,air-off,water-off”mechanism,easy handle and ... air and water supplies, check carefully if the wire clips are entirely and correctly set in the respective ... the back-head. Check frequently the wear on the clips and timely replace the worn-out or ...