1、More compatibility: wireless Bluetooth FM transmitter adapter for car radio, transfer calls, MP3 music, mobile phone voice to car speakers. Compatible with Bluetooth devices. 2、Hands‑free function: Built‑in microphone, automatically switch from music playing state to hands‑free mode when answering a call. One‑click answer, reject, raise hand, recall. 3、Car battery voltage function: display the voltage for 3 seconds when plugged into the car socket. Always keep the battery healthy. Then it goes to auto play mode. 4、Multifunctional transmitter, echo cancellation and noise processing during calls; Stereo Bluetooth and FM emission technology; Support USB, memory card (not included), Bluetooth function. 5、FM transmitter faster pairing and more stable sound than other common transmitter on the market, which can avoid unstable connection problems effectively. 1 x Adapter 1 x Audio Line Item Type: Car Bluetooth FM TransmitterMaterial: ABSModel: E5Color: GoldFunctions: Bluetooth Adaptor, FM TransmitterApplication: Cars1: Bluetooth Hands-free Call2: Echo cancellation and noise processing during the call3: Stereo Bluetooth and FM Emission Technology4: Support USB/Memory Card (not included)/Bluetooth Function5: Support MP3 Format Music6: Automatic Power off Memory Function7: Cigarette Lighter Power: DC12V-24V Voltage Power Supply8: Bluetooth Version 5.0 FM Transmitting Frequency: 87.5 ~108Mhz 9. Voltage Detection