1. Emergency unlocking: When the battery is dead, the Micro USB connector/3.5mm socket is used to connect an external battery box or power adapter. 2. Color: a variety of colors to choose from. 1. When the voltage is lower than 4V, it can be automatically unlocked and cannot be locked. 2. Two power supply methods: 4*1.5VAAA battery and 6V DC. If necessary, 12V DC can also be used. 1. Low voltage alarm: When the voltage is lower than 4.5V, there will be a sound and light prompt every time the lock is unlocked. 1. Installation method: vertical installation and horizontal installation, suitable for various occasions. 1. A variety of working modes are available: suitable for applications in different places. The user can use the mobile APP to control the lock..syi