Bluetooth 4.0 module is suitable for your applications requiring remote data transmission. In some projects, there are cases where you have to centralize data or remotely controlling equipment that is easy enough. For example, this way you can control household appliances or light in your home by using relays and brake Arduino development.
Specifications:
Voltage: 3.6V - 6V; Current Consumption: 18.6mA max (actively, TX, -6dBm); Minimum consumption is 0.4uA (external interrupts); Consumer power down mode with wake up 3us: 235U; Logic level RX / TX: 3.3V; Transmission distance: 60m; Reception to 3KBps.
The kit is designed to provide a visual representation of the audio signal level, making it easier to monitor and control the volume of audio equipment.