This wireless earphone is speically designed for sport.
Insert your TF card,you can use it play musics included in your TF card.
It also can be used to listen to the radio.
It is light weight and easy to use while doing sports.
If you forget your cardreader,it can be also used as a card reader by connecting it to a computer through USB cable.
Audio Formats: Mp3. Five buttons:Power on/off,foward,backward,pause,and mode.
Capacity: 128MB-32GB. S/Nratio: >=86dB.
Build-in TF Card slot.(Supports 1-32GB TF card
Power by USB cable. Output frequency: 20hz-20khz.
Built-in rechargeable li-on battery.
Compatible system:Windows 98/2000/XP/Vista/7
Weight: About 40g
Four colors for option:Black,Blue,Green,Blue
Sport MP3 x 1 USB cable x 1