The device is supplied with 2xAA batteries that drive the fan, which distributes the active ingredient. The use of the drug itself had an LR44 button cell on the edge. This probably covers consumption.The mission should last 90 days. I can not say anything about the batteries.The device can be operated without connection. Press button for about 1 second, also of. Double-click turns the device on with a 10-hour timer.Alternatively or additionally, the device can be controlled via the Xiaomi Home App.There can be various settings such. Set timer. The connection is established via Bluetooth. (for the first time press the button on the device for 5 seconds to pair) Then the connection can be made directly via the smartphone or indirectly via a Bluetooth gateway such as the bedside lamp, the alarm clock or others. Then the device is indirectly controllable from anywhere.The fan in the device is audible only if you keep your ear directly on it.