USB lithium battery charging, with 3 small buttons to set hours or minutes, the maximum setting time is 99 hours and 59 minutes. USB charging lasts for 120 hours. Once the lock is locked, it cannot be opened and it is impossible to do so by hand. Set the time reasonably. The padlock combination is lightweight and suitable for airport and travel security. You can lock your important items at any time to protect your privacy. Model Number: Smart Time Lock Function 1: LCD Time Lock Function 2: USB Rechargeable Temporary Timer Padlock If you find that you cannot use the timeout or the LCD screen is not displayed correctly, here's how for the timer: 1: Press the center of the LCD screen to remove the protective film and tear off the film. You will find a stop under a screw on the left side of the device. 2: Find a metal pin or metal clip and insert it into the hole, then push it in. 3: When you hear a "Bi" sound (in sound mode), the LCD screen will be displayed correctly. The timeout has been reset. 4: Stick back the protective film. Color: Black Material: ABS Package Contents: 1 x Time Lock Only the above package contents, other products are not included. Note: Light and different displays may cause the color of the item in the picture to be slightly different from the real thing. The measurement allowed error is +/- 1-3cm.