portable 110V and 220V welder with multifunctions: MMA, TIG,PULSE TIG,MIG,PULSE MIG,DOUBLE ... PULSE MIG 1).Dual voltage(110V and 220V)automatic recognize and self-switch over2).6 function ... in 1: mma,tig,pulse tig,mig,pulse mig and double ... 3).High frequency arc stating methods for tig welding4).Alternative wire feeding methods for MIG ...