The battery recharges through a USB interface and powers both the headlight and the MP3 player. Twist the ring to for song selection and volume control.
The headlight is a 1 Watt OSRAM LED providing 90-100 lumens in steady or flashing mode. I don't see anything in the specs on the MP3 player memory size.
English language product info and online ordering. At $109 plus shipping (from Taiwan?) I'm not willing to buy and try -- is this available in the USA at all anywhere? I saw this in a Taiwan bike magazine.