About this item BLUETOOTH V4.1: The latest Bluetooth 4.1+EDR technology provides lower power consumption and wider compatibility. You could enjoy your smart phone music or handsfree calling through your car stereo system. AUTO-ON & AUTO-CONNECT: This Bluetooth car kit will power on automatically when you start the car, then auto sync with the last connected phone (please make sure the Bluetooth of your phone is turned on before starting the car) THE GROUND LOOP NOISE ISOLATOR INCLUDED: In most cases, the sound quality is excellent. If you are bothered by the buzzing noise, you could use this noise isolator to avoid it. Dual Port Car charger included: Comes with a 10 watt dual port 2.1A cigarette lighter power adapter, stand ready to charge additional devices at the same time. CONNECT To 2 PHONES: With the multipoint technology, the Besign BK01 Bluetooth Car Kit can connect to 2 devices at the same time.