V8 Wireless Bluetooth 4.0 Headphone Music Stereo Phonetics Long Standby (Silver) Latest upgraded Bluetooth 4.0+APTX Headphones : Low-power & Low-latency provides high-fidelity and stereo music Compatible with most cellphone and devices with bluetooth capabilities.Retractable Earbuds :Easy to adjust the length of the line by only press a button ; the combination of human ear radian design and become High quality with HD speaker and enhanced BASS effect. Bluetooth transmission distance 10M Flexible design perfect Sport Wireless Headphone  Sweat-proof and rainproof ; Light weight. Support power status broadcast, real-time silent ;Built-in high quality microphone support various phone calls (by Wechat,Skype,MSN)