Driver size: 6mm/1/4\\\' dynamic driver Power supply: 5.0V 400mA Earpiece: 6.8g/pc (13.6g combined) Charging case: 45.4g Headset battery type: Lithium-ion battery (50mA/3.7V) Charging case battery type: Lithium-ion battery (300mA/3.7V) Charging time: < 2 hrs from empty Music playtime with BT on: up to 7.0 hrs Music playtime with BT on and ANC on: up to 6 Frequency response: 20Hz - 20kHz Impedance: 16 ohm Sensitivity: 97dB SPL @ 1kHz Maximum SPL: 96dB Microphone sensitivity: -32dBV/Pa @ 1kHz Bluetooth version: 5.1 Bluetooth profile version: A2DP V1.3, AVRCP V1.6, HFP V1.7 Bluetooth transmitter frequency range: 2.4GHz - 2.4835GHz Bluetooth transmitter power: