Companion for Non-Bluetooth Audio Device - This bluetooth receiver can be connected to non-Bluetooth audio equipment, such as car audio, home stereos, wired headphones, etc. via the 3.5mm AUX auxiliary adapter. Just pair it with your phone and start listening to your favorite music! Hands-free Calling - Built-in microphone and the MFB button help you to answer/redial/hang up/reject calls, offer you hands-free calls. The bluetooth adapter can be paired with 2 devices at the same time, then you can switch easily between 2 devices for call or music. Bluetooth 5.0 & Auto Connection - Equipped with a bluetooth 5.0 chip for stable connection/fast transmission/wide signal range. Once paired, the car receiver will automatically reconnect to your last paired bluetooth devices, as long as they are within the wireless range. Advanced Noise Reduction Tech - Adopted the latest CVC8.0 Noise Cancellation and Digital Signal Processor (DSP) technologies, the bluetooth audio receiver provides you with clear calling sounds. Long Battery Life & Type-C Charging - Up to 16 hours of use after full charged. And it can be fully charged within 2.5 hours by using a Type-C fast charging cable (Included in the package).