Lenovo ThinkPad X1 Active Noise Cancellation Headphones, Bluetooth 5.0, Battery Capacity 800 mAh, Battery Charging Time 3h, Play Time 14h, Wireless Operating Distance 10m, Impedance 32 ohm, Sensitivity > 111 dBm +/- 3 dBm, Distortion 5%, Microphone: 4 x analog microphones: Omni- directional, Sensitivity: -36 dB, SNR: 60 dB 2 x digital microphones: Omni-directional, Sensitivity: -26 dB, SNR: 59 dB, Controls: Power on / off, Multi-function button, Microphone muted / unmuted, Volume up / down, ANC level 1 / level 2 / off, Cable Length/Type: 1.3 m, Weight: 214 g, Black and Iron Grey