Features:- Safe and hands-free、 you can enjoy music through your car stereo. - Sleek design、 great touch feeling. - Backlit LCD screen clearly displays station information even in low light. - Easy to use and multifunction. Plug the car charger into the cigarette lighter and insert the AUX cable into your device's headphone jack、 then select a clear frequency. - Compatible with smart phones、 tablets and devices with a 3.5mm AUX port. Specifications Effective Range: approx. 15ft Frequency Range: 88.1-107.9MHz Dimensions: 1.35*2.36*0.49 inches Package includes 1 x Doosl FM Transmitter 1 x Usage Manual FAQ:1 Does the FM transmitter works without the audio jack of your car?Yes、 it will work. It does not need an audio jack in the car、 but your car must have the ability to capture FM radio signals.2 How do I run the Doosl? FM Transmitter?Simply operate the FM transmitter by following three steps:(1) Connect the Doosl? FM Transmitter in the cigarette lighter(2) Connect the audio jack on an audio player (such as a smart phone、 MP3 player).(3) Set the radio station in a frequency non-broadcast、 and adjust the Doosl? FM Transmitter at the same frequency.3 must often changed channels for not sizzling?(1) Be sure to find empty stations manually or websites such as Radio-Locator.com and SiriusXM.com. Just type in your zip code or lieu.Essayez each station to determine which one offers the best sound quality.(2) Make sure the volume is good、 the volume to about 3/4 seems to work best with FM transmitters.(3) Under the law、 we do not allow to improve the signal、 it is more difficult to find an empty station in the city.