Feb 14, 2022 · Nulaxy KM18: Check the current price. 5. Mpow Bluetooth transmitter and receiver 2-in-1. The top-selling Mpow Streambot Mini Bluetooth Car Aux Adapter is an inexpensive, versatile, hands-free, Bluetooth car adapter. It is lightweight and has a hi-fi, crystal-clear, noise isolator range up to (an unobstructed) 30 ft.