Kindly Note: It will sometimes pick up static please try to unplug and leave for a while and that does the trick.Specifications:- Bluetooth Version: V4.2- Frequency: 2.402-2.480 GHz- Effective Range: 5 meters- FM Frequency: 87.5MHz-108.0MHz- Micro SD Card/U disk capacity: Up to 32GHow to use:1: Plug the FM transmitter into your car cigarette lighter socket for power;2: Find an empty station and keep the FM transmitter and car FM radio at the same frequency. FM channels 87.5 MHz-108.0 MHz;3: Activate your phone's bluetooth and select ''T25'' to connect.Hands-Free CallsOne click the MFB button to answer/redial/hang up or reject calls; Seamlessly switches between incoming calls and music.Voice NavigationThis fm transmitter supports navigation App on your phone, you do not need to look down the phone to ensure safe driving.Dual USB Ports ChargingWith 2 USB ports(5V-3.1A and 5V-1A), you can get 2 of your devices charged simultaneously via this fm transmitter when driving.Note:To disable the Bluetooth for everything on your phone except the transmitter when you get in the car. Otherwise, it will affect the performance of the it.The Bluetooth FM Transmitter will connect to the last paired device automatically when turn it on next time.In order to prevent your car from being drained, please be sure to remove the device from your car after use.