Simple to use. Insert the card, charge it, and leave the device in the area you want to monitor, either on permanent charge or not. Send a message and provide the number that will notify you in case of a breach, then call the device's GSM number – it will open without ringing and you will hear what is happening in your space.
The device has a rechargeable battery and a 5V / 500mA charger.
Operating frequency: GSM850/900/1800/1900 MHz.
Note: The battery life in standby and usage depends directly on the quality of signal reception and may vary depending on the network, signal, and mobile carrier as well as the use of the device.