Bluetooth Keys Description:

1. Power on / off ; answer / hang up the phone; pause / play
2. Volume up? / next track
3. Volume down / previous track
4. Mic hole
5. USB charging port

Bluetooth Basic Parameters:

1. Transmission distance: CLASS ?
2. Operating range: 10 meters / 32.81 ft
3. Battery capacity: 180MAH
4. Frequency range: 20-20KHZ
5. Sensitivity: 95DB
6. Impedance: 32 ohms
7. Speaker size: 32MM
8. Charge time: 2H
9. Voice continuous talk time: 4-6H
10. Bluetooth music playback time: 3-6H ( 70% volume )
11. Hat color: white， blue， black， red