Sony WH-CH520 Wireless Bluetooth On-ear Headphones Features Digital Sound Enhancement Engine (DSEE) restores lost sound from compressed music sources Up to 50 hours battery life with Quick Charge (3 mins charging = 90 mins play) Designed with comfort in mind - adjustable headband, soft earpads and lightweight design (147g) Multipoint Connection - pair with two devices simultaneously e.g. phone and PC Bluetooth Ver. 5.2 with Google Fast Pair and Windows Swift Pair for convenient pairing Crystal clear hands-free calls with a high quality built-in microphone Connects to your smartphone's voice assistant (Siri / Google Assistant) Tailor the sound to your personal preference using the Sony Headphones Connect app (iOS / Android)