Synergic ControlOne - Knob Synergic Control Provides Appropriate ARC Voltage for the Welding current Selected.Easy OperationLess Buttons and Digital Setting Digital Indicator. Assured QualityCutting edge "Penetration Control" is one flip of the knob away.Fine ARC StartInstantaneous ARC Start Close to 100% From Low to High Current. ProgrammableUp to 30 welding conditions can be stored, 10 regular used conditions can be read and operate from remote control box.