The power of the concrete core drill is solid and stable It can variablespeed drill without shock dust and vibration The maximum speed is 980rmin, 1600r/min, 1700 r/min. The drill can give you excellent protection from overload and leakage with the personal protection . The unique shoulder rest is designed for comfortable handling Blowmolded carrying case included for easy storing classification and convenient carrying Compact extra grip design brings maximum power thrust In addition stepless speed switch is helpful to apply to different situations with corresponding speed The diamond core drill rig plays a vitally important role in installing air conditioners pipes stair railings, highways, etc.