Up to 9h of battery life per single charge + additional full charge from the case, for up to 18h of unconfined playback on the WF-XB700 wireless earphones Big on streaming? Our latest Bluetooth headphones chip transmits sound to the left and right wireless earbuds simultaneously providing a seamlessly stable and reliable connection to overcome vocal delays Headphones ready for every eventuality, with an IPX4 water resistance rating splashes and sweat won't stop these true wireless sports headphones These truely wireless earphones feature an Ergonomic Tri-hold structure for a secure and comfortable fit Easy-to-operate buttons let you control playback, access your smartphone's Voice Assistant and make hands-free calls on your Sony headphones