Brand: Hoco Model: EW72 Bluetooth: V5.4 Jerry AC7003 Support protocol: Headset Hands-free A2DP Avrcp Transmission range: 10 meters Transmission frequency: 2.4GHz Maximum RF output power (EDR): 4DB Modulation type (EDR): GFSK, π/4-DQPSK Speaker: 13MM Impedance: 32Ω±15% Frequency response: 20~20000Hz Sensitivity: 98db±3db Charging voltage: DC5V Charging time: about 1 hour Charging box battery capacity: 360mah; left and right ear battery capacity 30mAh each Talk time: about 4 hours Music time: about 4 hours Net weight: 57.6g (including charging compartment); bare device weight: 3.7g (single ear) Size: 60.6*45.2*23mm