Features SIZE DETAILS: Spot welding pen body size 25mm x 170mm, wire length 350mm, 3mm x 1.5mm x 40mm professional aluminum copper alloy welding needle. EASY TO USE: Equipped with an imported MOS transistor, the welder pen can carry a current of 550A, with an integrated design and can be used by connecting to a battery. GEAR ADJUSTABLE: The welding needle can be disassembled and replaced, with a 99 gear stepless adjustment, convenient to use. AUTOMATIC TRIGGER: Equipped with a trigger button that can be welded once, very convenient, with built in LED indicator light. APPLICABLE BATTERY MODEL: Suitable for 18650 batteries or 21700 battery packs. Check the model for better fit! Specification: Item Type: Spot Welding Pen Material: Nylon, Silicone, Copper Alloy Wire Specification: 12AWG silicone wire Power Interface: Copper ear Operating Voltage: 12V-16.8V Spot Welding Current: 80A-150A Power Component: 550A MOS transistor Shell Material: High Temperature Resistant Nickel Plated Strip Spot Welding Material: 0.1mm thick nickel plated welding wire Pen Size: Approx. 25 x 170mm / 0.98 x 6.69in Wire Length: Approx. 350mm / 13.78in Aluminum Oxide Copper Alloy Welding Needle: Approx. 3 x 1.5 x 40mm / 0.12 x 0.06 x 1.57in Package List:1 x Spot Welding Pen  1 x Nickel Plated Welding Wire   Package List 1 x Spot Welding Pen 1 x Nickel Plated Welding Wire