... 20kHzSize:540mm*500mm*1700mmFunction:it can not only use for drilling but also carving Characteristics:using AC220V power supply ... frequency according to the actual power,process simply no need for manual adjustment 2, overload, overcurrent, overvoltage, automatic protection 3, ... and save energy, no radiation, no pollution 5, suitable for processing jades, crystals, agates, glasses, hard alloys and all ...