https://alexnld.com/product/portable-10000mah-spot-welding-machine-small-handheld-diy-18650-lithium-battery-control-board-mini-nickel-spot-welder/?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"