pecification:
1.Bluetooth version: 5.3 version (automatically paired together)
2. Transmission distance: outdoor straight line distance 10 meters
3. Battery capacity: polymer lithium battery 40 mah
4. Charge box battery capacity:500 mah
5. Listening to music time: 3-4 hours (pause/play)
6. Talk time: 4hours (answer/hang up)
7. Standby time: 280 hours
8. Charging time: 2 hour
