* Once the main batteries are depleted, you can use the backup battery, no worries about dead battery and be locked outside. * Three unlock modes optional: Phone APP unlock, Remote control unlock, indoor Button unlock. * Remote controls with digital conversation system, it cannot be decoded or duplicated. Anti-theft and bring you safety. * Dual core and dual system, open faster, response quicker. Easy and firm installation with the external mounting plate. * No lock hole design, it completely abandons the traditional key and lock, open and close by remote control or APP (eWelink), realized real security.
