World's Smallest Portable Full Duplex Speakerphone            Omni-directional mic         Active Noise Cancellation       Echo Cancellation             Clips to collar,shirt pocket,or jacket

Bluetooth specification: V2.0 + EDR
Bluetooth protocol: HSF, HP
Frequency Range :2400-2480MHZ
Speaker driver: 1W/8 Ohm
Microphone Sensitivity:-44db
Battery capacity: 350mAH rechargeable lithium battery
Talking duration: 4 hours
Standby duration: 150 hours