Apple Shape Wireless Remote Control FM Transmitter with Car Charger for iPhone(White) High fidelity and frequency, stereo, digital pll LCD display with blue background lighting 200 selectable channels(88.1MHz~107.9MHz, 0.1MHz/Step) Muti-memorial channels, individual design to meet different requirements Small electric current, power supply by iPod, no need extra power supply Compatible: iPhone 4, iPhone 3GS Operating Instructions: Turn on iPone player, plug the FM transmitter into the connector port of iPone Adjust the volume and frequency of the FM radio(avoid the transmission channel of the broadcasting stations) Press “+" increase 0.1MHz frequency, “-" key decrease 0.1MHz frequency Choose the best frequency, then choose “1”“2”“3”key and press for 5 seconds. To keep it in your memory group.(if the sign is interrupted, please set the frequency of the FM transmitter and the FM tuner to some other frequency) Directly supply power for iPone, connect charger into the bottom of the device Packing includes: 1 x FM transmitter 1 x Remote control 1 x Car charger