Bluetooth 5.1 Earbuds with True Stereo System 3.7V lithium-ion earbud battery with 25mAh and 320mAH capacity Headphones Approximately 1.5 hours are needed for charging. Headphones Approximately four hours of work Working time of charging box: two to three times Headphones Waiting period of roughly 280 days Headphones Use the multifunction touch screen to answer calls, mute music, hang up, and adjust volume.