Adjusting frequency and volume: Supported frequency of the wireless radio adapter is from 87.5 - 108.0 MHz. You can adjust the frequency by rotating button. The key of CH is to adjust the frequency mode and key of < and > is to adjust the volume.
Playing music from TF card and smart mobile phone: After you insert the TF card into the car device, it will detect and play the MP3/WMA/WAV music in the TF card automatically. You can select songs by pressing < and >. It supports A2DP function. Similarly, it will transmit the signal to car stereo to play music from your phone. The music volume/ play / pause/ previous/ next can be operated either on mobile or on the mini bluetooth device. If you long press CH, the file source can be switched.
Connection to Bluetooth devices and memory funtion: This car kit device can connect to other handheld Bluetooth devices because the bluetooth FM transmitter is equipped with built-in Bluetooth chip. After you turn on the device, the pairing function will be activated automatically. Because of memory function design, it will automatically connect to its memorized paired Bluetooth device when it's on.
Charging handheld devices in car: Integrated car USB charger of output 5V - 1000mA is available and you can charge handheld devices in car.
Make/answer a handfree call: It supports Bluetooth hands-free phone calling for build-in microphone. When you have a call through it, noise and wind can be suppresses to create full duplex sound quality by CVC technology. After connecting it to mobile phone via Bluetooth, you can make or answer a call successfully with hands free car driving. You can activate redialing of a last number by double clicking the call button and reject an unwanted call by pressing the call button for about 5 seconds.