Long battery life of up to 25 hours. Splash-proof and sweat-proof with an IPX4 rating3 Easier, clearer hands-free calling Fine-tune your sound using the Sony | Headphones Connect app Easy to operation with buttons to play and pause, skip tracks and adjust the volume. A well-balanced shape around the neck ensures a stable fit. The WI-C100 headphones have a flexible neckband that fits to you. Sync your headphones easily with Fast Pair.4 Experience 360 Reality Audio for a truly immersive experience5