Specifications: BT version V5.3 Full Upgrade Working frequency: 2400MHz – 2480Mhz Max output power 4±1dBm(EIRP) BT Range: 10m (barrier-free open environment) Frequency response range: 20Hz-20Khz Music Time: About 6h (70% volume) Calling Time: About 4H (70% volume) Earbud Battery capacity: 30mAh Earbuds charging time: about 1.5h Case Charging time: about 1.5h Cycle counts: about 3.5 times Case power input: 5V 1A