Note:  1. After connecting to the power supply, a beep will be heard and the screen displays 0.  At this time, welding cannot be performed only after the output power (1-8 gear) is adjusted by the button.  2. 7V-16V voltage and 100-300A current are recommended, or it may damage the control board.   3. Welding tip: Put the nickel sheet on the surface of the battery electrode that needs to be burst, tilt the nickel sheet with one pen, then tilt the nickel sheet with another pen. The welding will be triggered after about 0.5s when the control board detects that the pen is placed. If the solder joint is black, turn down the gear. If the melting point is too small, increase the gear.      Specifications:  Material: Copper+PC+Electronic Element  Color: Green+Black+Red  Recommended Working Voltage: 7-16V  Recommended Working Current: 100-300A  Max. Welding Thickness: 0.15mm  Recommended Working Power Supply:   (1) 12V automotive starting power supply  (2) 30~35Ah capacity battery pack  (3) 12V 20~45Ah lead-acid battery with good performance  (4) 2S.3S.4S aeromodelling lithium battery pack  (5) 3-string high-magnification lithium battery pack  (* Charger, switching power supply and transformer can not be used as the power supply.)  Item Size: 9 * 5.6 * 1.5cm / 3.54 * 2.2 * 0.59in  Item Weight: 181g / 6.38oz  Package Size: 15 * 10 * 4cm / 5.91 * 3.94 * 1.57in  Package Weight: 210g / 7.41oz      Package List:  1 * Main Circuit Board  2 * Input Cable   2 * Spot Welding Pen  1 * Roll of Nickel Sheet (5m)  4 * Set of Stainless Steel Screw  2 * Heat Shrinkable Tube