Lectronic Earbuds PRO is an advanced and elegant earbud supporting long-duration calls and HD music experiences. The Earbuds PRO battery possesses a capacity of 30mAh. It has a single earphone use, free switch, and allows smart touch control and high sensitivity touching for music control-volume control- call control - voice assist. Its In-ear design is attractive, stable, and comfortable. It has the latest Bluetooth chip, 5.1, for a stable signal, with no delay. Earphone Bluetooth Version: V5.1 Supports Wireless Charging (5W). Speaker impedance:32Ω Music time:4H(80%volume) Talk time:3.5H(80%volume) Frequency response:20Hz-20KHz Charging Case Earbuds battery capacity:30mAh Case battery capacity:280mAh Supporting protocols: HSP/HFP/A2DP/AVRCP Driver:13 mm Charging input port: Lightning USB Charging frequency: 3-4 times Earbuds charging time: 1.5Hrs Case charging time: 2 Hrs Tri-color charging LED indicator. Low battery alarm.