1. Plug car charger into car cigarette lighter socket. Car charger adapter with USB 5V/1A output port which can charging for other cell phones digital products. 2. Switch "+" / "-" to adjust the FM band select the frequency 3. Plug the 3.5mm connector into your IPHONE IPAD Samsung and other cell phone with 3.5mm jack. 4. Open the music from your cell phone so that the car audio system can play the songs from your cell phone. Performance: - Suitable for IPOD IPHONE Samsung and other smart phones - Input voltage: 12~24V - Charging output voltage / current: 5V / 1000mA - Working current: 50mA