... , WS-500 Manuel and argon welding machine1Advanced inverter technology, a machine for TIG and manual metal arc weldi2 ... .High-frequency booster arc, easy arc starting, welding current stability, fast dynamic response, low spatter, ... good weld appearance4.Stable and reliable, energy efficient, small size, light weight5. ... cooling 1L/min WS-400 Manuel and argon welding machine