G-Cord Bluetooth 4.0 Headphones Sweat-proof Wireless Stereo Sport Running Headsets for iPhone, iPad, Samsung Galaxy, Tablet Flexible, lightweight and sweat-proof design, remain comfortable even when soaked in sweat when running, jogging, cycling, and working out Easy functionality controls are on the earpiece. With built-in microphone for phone calls when you are doing excises or outdoor activities Bluetooth 4.0 version provides high-fidelity stereo music and clear speech, supports multi-connection for simultaneous use of the headphones with two mobile phones Behind the neck and over the ear design secures and comfortable fit your ear or head G-Cord headsets are compatible with most Bluetooth-enabled Smartphones, up to 6 hours of calling, 5 hours music playing time and 200 hours standby, let you enjoy your music through a variety of activities