Gear control: Range 099. Gear 1 is the lowest setting and gear 99 is the . Increase gears sequentially during use to adjust welding current precisely. Bilateral outlet: Dualoutput design for convenient spot welding. Terminals are clearly marked to minimize incorrect connections. Battery and cell compatibility: Suitable for cylindrical lithium batteries including 14650, 17490, 18650, 21700, 26650, 32650, etc., as well as nickel metal hydride batteries. Can reliably spot weld these cells with firm results. Nickel sheet compatibility: Supports spot welding with 0.10.3 mm nickel sheet. MOS tubes and upgrade potential: MOS tubes x5 included. Five MOS tube positions are reserved on the back of the PCB. Maximum current potential: After five parallel connections, the theoretical maximum current can reach about 1700 A, reflecting strong current capability for demanding welding tasks. DIY friendliness for electronics enthusiasts: This design is convenient for users familiar with electronics and handson hardware. Use scenarios: Build or cylindrical Liion battery packs (for example using 14650, 17490, 18650, 21700, 26650, 32650 cells) by spot welding nickel tabs and nickel strips. Assemble custom battery packs for devices or projects that require reliable, current spot welding of lithium cells. Educational or hobbyist projects where users want to upgrade or experiment with MOS tubes and current levels for handson learning and performance tuning.