Circuit board soldering pen spot welding machine, used for welding lithium batteries, is a must-have DIY product for beginners. This circuit with a battery will become an energy storage spot welding machine for welding nickel pieces. Good performance and small internal resistance. Features - Color: Assorted color. - Material: Copper. - Size: 10.00 x 5.00 x 3.00cm/ 3.93 x 1.97 x 1.18 inch. - Wide selection of welding power sources, lithium battery power supply or 12V car battery. - The controller is controlled by a single-chip microcomputer, and the output pulse is accurate to ensure the quality of welding. - It is precisely controlled by the single chip microcomputer program without flipping the switch. - The controller has an LCD display screen that can display welding parameters. - The soldering pen and the input line are connected by U-shaped cold-pressed terminals, which is convenient for disassembly and replacement.