Timer Lock with USB Charging USB rechargeable lithium battery powered, with a display screen and 3 small buttons to set hours and minutes. Maximum setting time is 99 hours and 59 minutes. A single USB charge provides up to 120 hours of use. Once locked, it cannot be opened manually. Set the timer appropriately. This combination lock is lightweight and ideal for airport and travel security. Secure your valuables anytime, protecting your privacy. Resetting the Timer Lock: If the timer isn't working or the LCD screen isn't displaying correctly, follow these steps to reset: 1. Press the center of the LCD screen to remove and peel off the protective film. You'll find a recessed screw hole on the left side of the screen. 2. Insert a metal pin or clip into the hole and push. 3. When you hear a "Bi" sound (in sound mode), the LCD screen will display correctly. The timer has been reset. 4. Re-attach the protective film. Weight: 30g Color: Black Material: ABS Package Contents: 1 x Timer Lock Note: Light and different displays may cause the color of the item in the picture to differ slightly from the real thing. The measurement allowed error is +/- 1-3cm.