Realme Buds Air HIFI sound Bluetooth is enabled on both left and right so that it can be used separately. The Ear Bud has a 300mAh rechargeable Li-ion battery that can play for 2-3 hours of playback time, about 4 hours of talk time, and 6 hours for both ears. It can connect to mobile devices from a distance of 15 to 25 meters.