Features:- Bluetooth V4.1- Portable lightweight and sweatproof design- Built-in microphone- Built-in rechargeable Li-ion battery- Multipoint pairing (connect 2 bluetooth device)- Support voice prompts ( in English， Chinese)- Support voice reporting Phone NO. - Support Multipoint 1 in 2. ( connecting with 2 bluetooth device in the same time)- Built-in 14.2mm nedymium driver- Clear bass resonance， CVC wind noise reduction， and superior sound isolation- Support power display for iphone- Support listen musice， last song / next song switch， turn up / turn down / pause. - Support switch into answering phone when listening music Technical Specification:-Bluetooth specification: 4.1+EDR-Bluetooth profiles: Headst HFP A2DP AVRCP-RF range:10m-Noise reduction:CVC6.0-Stand- by time:about 175 times-Calculation conversation time:bout 5 hours-charging time: about 2 hours-Dimension(LXWXH):5.7X2.3X0.9cmPackage:1 X stereo Bluetooth Headset1 X Use Manaul