1. Bluetooth MP3 function support stereo music playing, phone calling...
2. Support all audio devices that have Bluetooth capability, such as, cell phone ,tablet PC,laptop,computer etc.
3. 3.5mm audio jack, provides a simple wired connection of a variety of devices without Bluetooth.
4. Allow you to answer or reject phone calls anytime and anywhere.
5. Charged via USB, rechargeable battery, convenient and practical.
6. Playing time up to 8~9 hours, and continue talk time up to 8 hours, standby time up to 250 hours.
7. Good quality, foldable design and adjustable length hinges, very comfortable to wear and easy to carry.
8. Best choice for listening music, watching movie, chatting online etc.
9. with SD card insert,without any bluetooth device,can still enjoy music any time any where.
10.Cool shinnging outlook adds the fashionable feel.
Version    V4.0
Frequency    2.40GHz-2.48GHz
Power    ≤ 4 dBm, class 2
Effective range    10M
Sensitivity    -84dBm / 0.1% BER
Frequency response    20 Hz - 20 KHz
S/N rate    70 dB
Distortion    0.10%
Speaker size    40mm 
support    A2DP 1.2, AVRCP 1.0, HSP, HSF 1.5
Voltage    3.7VDC (built-in 400MAH rechargeable battery)
talking time    8~9 hour
standby time    250hour
charge time    2-2.5 hour
current    40 mA
operate temperature    -4 ~  131°F(-20 ~  55°C)