The Calrad 40-BT4 Bluetooth V3.0 Stereo Audio 2 in 1 Transmitter and Receiver options provides 30 ft. of wireless connectivity. Easily pairs with all Bluetooth compatible devices. When the 40-BT4 is set to Receiver (RX) mode the Bluetooth wireless receiver can decode audio to the 3.5mm line output jack that can easily connect to a home stereo or PC line input for wireless Bluetooth audio, play music from any Bluetooth A2DP enabled mobile phone or other Bluetooth A2DP audio devices. Listen to your audio in comfort without a wired connection, Also in RX mode you can remotely play and pause content. When the 40-BT4 is set to Transmitter (TX) mode the Bluetooth wireless transmitter can transmit Bluetooth A2DP audio using the same the 3.5mm line input jack to AV stereo receivers and other compatible Bluetooth receiver devices.