7 inch Max Drilling Diameter 2180W powerful motor of the handheld core drill rig is designed for wet drilling in reinforced concrete stone asphalt marble ceramic walls floors and more With a 7"/180mm max drilling diameter and 1600RPM stepless speed, you can drill with less effort. Steel Output Shaft & Copper Inlet As the machine will work upside down water will unavoidably flow on to the drill machine In this case our drilling rig has a rustproof steel forged output shaft and copper water inlet for a longlasting water supply Overcurrent Protection We also provide an overload protection and an upgraded cooling. They are designed for avoiding burnin and prolonging the service lifespan of the drilling press machine Comfortable Shoulder Rest & Handle The upgraded shoulder rest is designed to save your energy The slipproof rubber handle greatly enhances friction and reduces vibration to completely control the hammer with comfort Besides tools are well stored and sorted in a compact case Wide Range of Application The wet diamond core drilling rig can be widely used in drilling reinforced concrete red brick marble and other materials It is for installing air conditioners, pipes, stair railings, repairing highways, etc.