General Spec Function provide a stable support and charge your device Compatibility Apple iPhone 4G Features Elegantly and compactly designed white docking cradle, perfect for your iPhone 4G. You can connect the dock to your computer with the cable that came with your iPhone, then place your iPhone in the dock to sync and charge the battery. Also connect the dock to an electrical outlet using a USB power adapter, then charge your battery. Enjoy your music from iPhone by using a stereo audio cable to connect the dock to a stereo or speakers. The cradle charger holds your iPhone firmly in place while providing full access to the keyboard and side buttons. Line out for audio. Non-slip pad is attached to the bottom for firm standing.