Awei T77 ENC Bluetooth Earphones Noise Cancelling Earbud.

Rotating charging case (mechanical feeling when decompressed) Bluetooth chip: JL6973D4 Bluetooth version: 5.3 Supported protocols: A2DP, HFP, AVRCP Battery capacity of earbuds: 30mAh*2 (no protection board, protection IC) Battery capacity of charging case: 250mAh (with protection board) Diameter of horn: 13mm Charging time: 1.5h Talk time: 3h Playing time: 5h Standby time: 300h Horn sensitivity: 116 ± 3DB Horn impedance: 32Ω Standard input voltage: DC 5V Bluetooth operating frequency: 2.402GHz ~ 2.480GHz Frequency response range: 20Hz to 20,000Hz Maximum transmission distance: 10m