Model BT550
Functions: Stereo bluetooth +TF card MP3 Player+FM Radio+Line-in
Bluetooth Chipset: ISM Band
Bluetooth Version V3.0+EDR  
Sensitivity 2.402GHZ~2.480GHZ
Frequency Response 20HZ-20KHZ
Transmission Range 10M
TF card MP3 Player: Can playing MP3 music by inserting TF card.
TF card capacity: Support max 32GB
FM Radio: Frequency 87.5~108Mhz
Mini USB Charging Port
Output Power 2X10mW
Speaker Unit : 40mm
SNR 80db
Battery 300mA
Working Volt 3.7V

1XUser manual
1XAUX input cable
1XMini Usb Charger
1XFoldable Stereo bluetooth headset

Features:
Streamline design make your headphone look more comfortable and beautiful
Foldable and adjustment， fit for your every demand， adjust the length your need to suitable your braid.
High quality sound， you can enjoy the music when you are sporting， watching book，take a bath
Compatible with 99% device own bluetooth function，like ipad， iphone， cellphone， Pad

Pictures: