Big Bouncing Bass: 12mm composite drivers intensify your music into a workout-fueling, bass-driven soundtrack. Sweat Proof: Push your workout to the limit with zero hesitation thanks to IPX7 water resistance and sweat guard technology. Keep it Together: When you're not listening to music, Sport Air clip together with magnets to stay secure and comfortable. Engineered for Comfort: When you're pushing your body through the wall, Spirit Air will stay strong and comfortable so you can focus on stretching your limits. Secure-fit, ergonomic design, and controlled entirely from the right earbud; with no rubbing or pulling from an in-line remote. Huge Stamina: get 10 hours of playtime. That's over a week of gym time from a single charge. Hands-Free Calls: A built-in microphone detects and isolates your voice for a great call experience, even in noisy places.