Bluetooth Headset, Wireless Bluetooth Stereo Earbuds Headphones Earpieces In-Ear Sweatproof Lightweight HandsFree with Mic for iPhone/Samsung/Android Cell Phones the bluetooth version: V4.0 V3.0 + EDR compatibility, V2.1, V1.1 the transmission power: Class2 transmission distance, more than 10 meters . the transmission frequency: 2.4 GHz,transmission distance, more than 10 meters . support the file format: A2DP music playback, headphones and hands-free mode.