OnePlus Bullets Wireless Z E304A Features Warp Charge Bass Re-engineered IP55 Water & Sweat Resistance A 10 minute charge for 10 hours of music Your Bullets Wireless Z series headphones are ready before you are. A single 10 minute charge gives you 10 hours of music and movies4. A full charge provides up to 20 / 17 hours1 of battery life, so you can keep the music going. Easy listening With convenient features like Quick Switch, Quick Pair and Magnetic Control, listening to your music has never been this simple. Bass Re-engineered With a 9.2mm dynamic driver and super bass tone fitted in each earbud, you get to experience rich sound and superior tonality every time you press play.