Took me a while to work out how this works - but pretty clever if you want to wear headphones and be able to talk bluetooth to a phone. Pretty good review here http://www.macworld.co.uk/ipod-itunes/reviews/index.cfm?reviewid=2411
Maybe a lille old / end of line but for a fiver all in pretty hot ??
# High performance stereo headphones/mono headset.
# Corded connection to your music player with a standard 3.5 mm jack.
# Use your own headphones as your hands free kit.
# Bluetooth connection to your mobile phone.
# Music fades when a call comes in.
# Operating range: Up to 10 meters
# Paired devices: Up to 8, one at a time
# Talk time: Up to 8 hours
# Standby time: Up to 240 hours
# Charging time: Approximately 2 hours
# Weight with headphones: < 40 g
# Dimensions, main unit: L63 x W26 x D12mm
# Microphone Sensitivity: -19 dB +/- 3 dB (1kHz, 0db=1V/Pa)
# Headphones Frequency: 20-20000 Hz
# Rain shower proof: Yes (IPx2)
# AC power supply: 5VDC, 0.25A output, 100-240VAC, 50-60Hz input