The Advance Series 3 Phase MMA (Stick) Welders include the latest IGBT technology & high tech features for industrial use. IGBT means increased reliability and performance for demanding industrial conditions. Bulletproof overspec Internals factory tested to 550V and IP23 External (abuse) rating. Ð High 60% duty cycle @400A Ð Phase loss protection Ð Designed for using cellulose welding rods Ð Selectable VRD Protection for increased safety Ð Damage resistant industrial casing Ð Microprocessor control system for superior and dynamic arc characteristics Ð Adjustable arc force, hot start & anti-stick control Ð Digital current display meter for accurate pre-setting and feedback of welding parameters & output.