The sleek curves?? vivid graphics... every detail is carefully considered for unique look.</br>HD Diaphragm technology lets you hear the difference even in your favorite tunes.</br>With 3D Sound on?? the sound stage is extended to complete an immersion feeling.</br>The headband isn't simply twistable?? it's ultra-flexible to reduce wearing pressure.</br>Up to 20 hours of Bluetooth playback from late"luetooth 4.1 low-power technology</br></br>Product Description</br></br>We know you are particular about headphones: you want them to be outstanding in performance?? also to be stylish in look. But we're bold enough to take this challenge?? and Bluedio A (Air) comes along. Our Bluedio A (Air) wireless headphones deliver your music with incredible depth and clarity?? and get you noticed with stylish look. <br> <br><B>Compatibility</B> <br> The Bluetooth perfectly works with your smartphone?? tablet or Bluetooth enabled MP3 player. <br> <br><B>Instruction tips</B> <br>Turning 3D sound on: when the headphones are playing music via Bluetooth?? press the MF Button and Vol+ Button together then release the buttons immediately. You will hear an indication note?? the 3D sound is on. <br> <br><B>Warranty and Custome