Enjoy a better wireless experience with this Kusen around-ear headphones. Exclusive technology delivers your music with deep, immersive sound at any volume, making them the 40 mm bestsounding wireless headphones available. An advanced microphone system, HD Voice and adaptive audio adjustment provide clear calls in windy or noisy environments. And enhanced sidetone makes your voice sound more natural, as if you werent wearing headphones. SoundLink wireless headphones use the latest Bluetooth technology so you can easily connect to your mobile devices with seamless audio/video sync. And you can switch between two devices, so you can watch a video while staying connected to your calls.