Boshi Electronic Instrument&reg; 709A LED Pulse Battery Spot Welder Spot Welding Machine 110V/220V Supply Voltage for 18650 16430 14500 battery pack Supply Voltag:AC 220 V  20 V/110V Power/Current:1.9 KW (Instantaneous)/500A Suitable Welding Thickness:0.03 - 0.3 mm for Fixed Copper Head/0.03 - 0.2 mm for Mobile Welding Pen Output Voltage:20V DC Temperature:150C ~ 450C