DGBAY&Acirc; Bluetooth Wireless 30-Pin A2DP Music Audio Receiver Adapter for Bose SoundDock iPod Nano iPhone 4 4S 5 Macbook Pro Dock Speaker DT-3401 Easy to use by connecting directly 30-pin dock to change the common sound-box to Bluetooth sound-box Support digital products using Bluetooth ,such as iPad, iPhone, Bluetooth cell phone, Bluetooth PC. Complies with Bluetooth 2.0, Support A2DP v1.2 Powered: via target device ( docking station) LED: One LED for paring and charging status Transmission distance: up to 10 metersNo obstructions