This inverter MIG welder is both MIG, and a self-shielded flux-cored welding machine. The MIG155GSV is equipped with a unique electronic reactor circuit, which can precisely control the short-circuiting transfer and mixed transfer resulting in better performance than other welders for sale. You will see the many advantages when you compare our products with silicon controlled welding machines and tapped welding. Our MIG welders incorporate a special advanced circuit designed to automatically sense if the user is actually welding or simply feeding a new roll of wire through the cable. The circuit detects either high welding current flow or the lack of high current flow. If after approximately 5 seconds of checking at slow wire feed speed, if no welding current is detected, our welders automatically run the feed motor at full speed to help the user more quickly feed their new reel of wire through the cable. Never try to set wire speed by pointing the torch into the air and pressing the trigger. That action will invoke our automatic high speed feed feature. The Weldpro 155 series are also portable, energy-saving, and electromagnetic noise-free. Besides, we stand by our products. They spatter less, have easier arc starting, a deep welding pool, and a high duty cycle that you will appreciate. Remember our support is always available to help and answer your questions