This mini-Bluetooth music receiver is very easy to use. Everything is done with a single button on the device. You can answer a call and connect at the touch of a button. Built-in rechargeable battery, up to 5 hours of playback and talk time, charging can be completed in about 2-3 hours. Connect to this Bluetooth receiver via a 3.5mm audio cable/adapter, then pair your phone or other Bluetooth device to easily listen to music and more. Instruction: First, hold down the button for about 3 seconds and release the button when the LED starts flashing red and blue or when you hear it confirmed by the device out loud. Then search and select "Bluetooth Music" in the Bluetooth settings of the device, the blue LED will blink after a successful pairing, and you will have it confirmed by the device loudly. Once the initial connection is successful, the Bluetooth receiver can be paired automatically. For all portable devices with 3.5mm car system/home stereo audio jack. Compatible with most smartphones and electronic Bluetooth devices, both iPhone and Android phones. Use e.g. Spotify wirelessly to the car's speakers through the adapter. NOTERA Cannot be charged and used simultaneously on some devices.