Features: Portable spot welding machine with quick release welding pen. The integrated soldering pen uses gold-plated terminals, with good conductivity and low contact resistance. Miniature USB charging interface is adopted for easy charging. Built-in high-speed battery 2 has excellent charging and discharging performance. .Fine workmanship and good performance.Easy to use&Long service life.. Specifications: Material: Metal. Size: about 105x83.2x28.8mm/4.13x3.27x1.13in Battery: 2xhigh-speed battery Output voltage: 4.2V maximum Output current: 639A maximum. Instructions: 1. Press and hold for 3 seconds. When the buzzer sounds, it is turned on/off. 2. Press the button briefly. If the buzzer sounds, it is the shift position. Press once to increase the first gear. For 1-9 cycles, the ninth gear is the strongest welding strength. 3. After placing the welding pen, the buzzer sounds. Wait about 0.5 seconds to trigger welding. 4. When charging, the power indicator flashes. When all four indicators are on, it indicates that it is fully charged. Welding can be carried out when charging. Note: Do not for touch any metal parts of the fuselage with a welding pen. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Thank you. Due to the differences of camera equipment, light intensity and display screens, the color of the item may be slightly different from that shown in the pictures. Package includes: 1 Setx Mini Spot Welder