Stunning sound and longer battery life Enjoy high-quality sound all day long. The WH-CH520 earphones with up to 50 hours of battery life, stable connectivity and enhanced call performance meet the demands of your day. Stay powered for days With up to 50 hours of battery life, you can listen to your favorite music without worrying about running out of charge. And, if your headset battery is low, a quick 3-minute charge can give you 1.5 hours of listening time. A listening experience just for you Digital Sound Enhancement Engine (DSEE) restores the harmonics and vibrancy lost in typical music compression for a more authentic performance. You can even customize the music to your liking with the equalization settings in the Sony Headphones Connect application, for a personalized listening experience. Crystal clear calls A built-in microphone gives you hands-free calling, and it works just as well for joining an online class or a business meeting. Designed for all-day comfort Not only is the design sleek, it's also built with ease of use in mind. The lightweight, swivel earcups slip on and off smoothly, while the adjustable headband, cushion and soft earpads keep you comfortable all day long.