Mini 503 Bluetooth Wireless Type Headset Stereo Earphone ,Mini-503 Bluetooth V2.1+ EDR Stereo Behind-the-Neck Headphone 
Feature:
Long talk time,all phones universal, Music player with A2DP
Function Keys : Volume + -, music playback, pause, previous song, next song
Supports all bluetooth devices,then hang up, reject calls, last number call-back
 
Specification:
Model:Mini 503
Weight:40g
Voltage:3.7V
Color: red, blue,champagne,white,golden
Channel :stereo
Talk Time:14 hours
Main Chip:3.0 + EDR
Speaker:30 speaker
Standby Time:250 hours
Bluetooth Version:V3.0 + EDR
Compatible With :V2.1, V2.0, V1.1
Charge / Discharge protection:IC
Battery Rechargeable:Lithium Polymer
Frequency Range :2.4G
Frequency Response Range:20-20KHZ
Transmission Power:Class2
Transmission Frequency:2.4GHz
Transmission Distance:10 meters
Average Sensitivity:105DB (AT 1KHZ +3 DB)