Renogy BT-1 Bluetooth Module Solar Charge Controller Wireless monitor PV System Wirelessly monitor and control compatible solar charge controllers via Bluetooth Connect to user-friendly smartphone app, Renogy BT, to keep track of your system Embedded exclusive Bluetooth chip with high efficiency and low energy consumption With Bluetooth 4.0 and BLE technology, it features fast and uninterrupted communication Powered directly through RJ12 communication port and Signal range is up to 50 ft