... rock hole blasting 2. 3 drilling speed 3. Strong impact 4. Low air consumption,noise 5. Rubber handle grip —Y20 Hand-held ... operation during operation.—YT28 Air-leg Rock DrillGrouped control mechanism, quick to start up with air-on, water-on, air-off mechanism easy handle ... upon your demand. MAXDRILL mining machine new type save energy air leg YT28 rock drill