Adtec has created one of the smallest bluetooth sets in history called the ADHSM10. It has two colors to choose from which are Silver and Titanium, a talktime of 3hours and 100 hours of standby, Charging time 2 hours , Communication distance of about 10 m, Compatibility Profile HSP (Headset Profile), HFP (Hands-free Profile), Power Built-in lithium-ion battery, and Security 128bit encryption / authentication PIN code. Look for this bluetooth in late January for roughly $78.
