d:e developed the Nantenna module concept for its in-house Shadow and Light brand. The iPod Nano's FM radio uses the headphones' wire as an antenna, but this approach does not allow the radio function to work in a speaker dock. The Nantenna module adds a physical antenna, speaker, and pass-through dock connector. Now, you can use the Nano as a small table-top radio or add radio functionality to any speaker dock.