The creator ‘teaches you welders’: first a JX-D99 welder board (a toy) + welding pens, hooked to a battery, five MOSFETs underneath; it felt underpowered so he added MOSFETs at the back, and after a dozen or so welds it blew; bought another and it still didn’t feel up to it; then switched to an AWithZ welder, model UF20B, 1750A, 5000W instantaneous (nameplate: 6.0V MAX, 1750A MAX, 10.5kW MAX, 100–240V, Shenzhen Juequi Technology); test-welded two pieces of 0.1-thick nickel strip — welds very good, bright and clean. Comments: ‘so the conclusion is you bought a welder for a few hundred bucks’, ‘you’re teaching us to buy a welder’, ‘talked into buying yet another one’; someone says Xiaoqiang’s can reach 2500+; someone claims a 5-MOSFET board with a 4S 120C battery at gear 75 can weld 0.1 nickel stacked on 0.5 copper (creator: no way).