Bluetooth Earphones, EGRD New Super Cool Design Apt-x Bluetooth Stereo Sports Headphones with Double Battery, Sweat-proof and Stable In-ear wireless Headset Support Hands-free . (Black) Double Battery : Built-in one battery on each earbuds. Super long using time. Up to 8 hours of music time. Low power consuming, free worry the earphone will runs out of juicewhen you exercise out or traveling. Latest Bluetooth 4.1 technology support Apt-x, CSR8645 chip. High-fidelity and natural Stereo Sound provide unparalleled listening experience. The CSR8645 chip support Voice recognition function(Or Siri ), enables true hands-free use. The most important feature is it more save power, and only need 2 hours changing time. Super Cool and Sport Design. Flexible and adjustable earhook. Comfortable and stable. No need to worry it will fall out of your ear when exercising. If you have any question about our product, please feel free to contact us. We will be happy to service for you.