Features: 1. Design of touch buttons， led screen， more convenient to choose. 2. High Fidelity， digital PLL create stable inheritance in a different environment. 3. The full frequency range， up to 200 for the option. 4. Memory for last frequency. 5. Powered by rechargeable built-in lithium battery， no need to use other equipments\' power. Operating Instructions: 1. Connect the transmitter device to a compatible device. 2. Change the fm transmitter to the same frequency with the car radio， or turn on the car radio to the same frequency fm transmitter. 3. Adjust the volume of both devices to an appropriate level that you need. 4. Play music or answer a call on the mobile phone side. Specifications: 1. The wireless signal range: max. 10 meters app. 2. Plug headphones: 3.5mm male 3. Dimensions: 59x20x10mm app. 4. Fm frequency range: 87.5-108.0 MHz 5. Compatible for ipod / iphone 5g / 4S / 4g / 3gs / 3g， sumsang galaxy S3 / S4， MP3 / 4 players， and other mobile phones. Package includes: 1 x fm wireless transmitter 1 x USB charging cable