... tool 2.suited to work on places without power supply pneumatic rock drill/jack hammer different types (YN27,YN30,YNF30,Y24,YT28,DGN21 ... a small petrol engine, an air compressor and a rock drill. 2. During operation, the rock powder is blown away by the compressed ... to work on high mountains, and places with no power supply and air compressing equipment, and especially suits the temporary projects that ...