FAST WORKING: This portable soldering iron adopts 5V DC power supply and using the special internal heat type soldering soldering head, heat fast and concentration. Heating up in less than 15 seconds, Cooling down in less than 35 seconds, which can greatly improve your work efficiency. SAFETY PROTECTION: When it is not working for more than 25 seconds, the indicator light will turn off and enter standby mode automatically. This function can better prolong the service life of welding head and save power, and it is safer. PORTABLE: This USB soldering iron is small and lightweight, it is convenient to put in your tool bag and take to your working place. USB cable, which can be powered by computer, mobile power supply or your mobile phone charger and so on. EASY TO USE: Cordless soldering iron has a reminder light on power button. Press the power button, the indicator light is on.The voltage knob can be adjusted in both directions, and the temperature of the soldering iron can be adjusted. There is an adjustment voltage knob at the bottom, and the adjustable range is 3.3V-4.8V WIDE APPLICATIONS : Soldering iron can widely used for circuits of small gauge, appliance accessories, welding, jewelry repair, DIY lovers and so on. Convenient and practical, it is a perfect gift for your friends who need it.