USB lithium battery charging, with screen and 3 small buttons to set hours or minutes, the maximum setting time is 99 hours and 59 minutes. USB charging lasts for 120 hours. When the lock is locked, it not open and it is impossible to break it by hand. Please set the time reasonably. The padlock combination is and suitable for airport and travel safety. You can lock your important items at any time to protect your privacy. How do I reset the timer lock? If you find you can not operate the timeout or the LCD is not displayed. correctly. Please follow this way to timer: 1: the center of the LCD screen to strip the protective film and tear the film off. You find a stop under a screw on the left side of the screen. 2:Find a metal pin or metal clip and insert it into the hole to and then run it. 3:When you hear a "Bi" sound (in sound mode), the LCD display correctly. The timeout has been successfully reset. 4:Please glue the protective film back on. weight 30g. colour:black Material:ABS