Let the sound track begin with the ultra-thin and foldable adina! Pair this wireless v 4.0 csr stereo headphone with your computer or smart device and enjoy an incredible 25 hours of playback on a single 3 hour charge! If you need unlimited playback, then use the 3.5 mm audio cord feature. You wont have to remove this comfortable headphone when your phone rings because it also has a built-in microphone that allows you to answer mobile calls. Branding options are available on the zippered case, headband and ear cups. spectech-sound products have a one year limited warranty on electronic parts from date of purchase