https://alexnld.com/product/multi-functional-portable-spot-welding-machine-diy-battery-welding-assembly-18650-lithium-battery-nickel-sheet-spot-welding-machine/?hilite="5000W Mini Spot Welder Kit DIY 18650 Battery Pack Welding Tools Portable Spot welding Machine Pen for 0.1/0.15/0.2/0.25mm Nickel Strip"