Features:FM Transmitter for i4S 5 6 3G / 3GS / 4 and other MP3 / 4 players，mobile phones.Hands free talk function offer you more safty during driving.LCD displayers frequency with backlight.With Touch key design，High fidelity stereo.Digital PLL，transmisson is stable in different environments.Full frenquency range.Memory for last frequency.Powered by rechargeable built-in lithium battery，do not need to use the iPhone's power.Blue LCD backlight display.Frequency range: 87.5 - 108MHz/StepSpecifications:Cable length: about 30cmColor: BlackPackage included:1 x FM Transmitter1 x USB to Micro USB Cable