The Tracks Air wireless headphones by Sol Republic transmit audio via Bluetooth from up to two devices with up to 150 foot transmission range. The rechargable battery can run for up to 15 hours. The dual device connectivity allows for you to take a call while watching a movie on another screen simultaneously. The Tracks Air come in 4 different colors, and work with the Sol Republic Remix Headbands which are interchangeable bands to customize the look of your device.