Conforms to the shape of the ear for comfortable and secure fit The memory wire securely holds its shape so the earphones won't fall out on-the-go It has ergonomic design & high grade silicone ear muffs Bluetooth 4.1 enables fast and stable connection during call and music within 10 meters. 70mAh Li-Polymer battery streams up to 3 hours of music and only needs 1.5 hours to fully charge, providing you with a whole day's worth of music