Thank you for your support to Tinydeal.
For the FM transmitter, you can use it by the following steps:
1, Plug the unit into cigarette lighter in your car .
2,Connect input connector in the unit to your portable device output jack and adjust the portable device output to proper level by volume control.
3,Turn the frequency of FM receiver in your car to the frequency labeled on the unit and you can enjoy fantastic music in your portable device now.
Any other questions please feel free to contact us on https://help.tinydeal.com/contact-us. And we would answer you within 24 hours.
Have a nice day!