easy listening: adjust the volume, change tracks, and take calls with on-device touch controls. a dedicated button for your device’s native voice assistant makes operating your headphones even easier. background noise control: advanced active noise cancellation reduces both high- and low-frequency background noises. transparency mode lets you tune back in to the outside world with a swipe of the touchpad. a sound experience: with a bass port for deep sound and two dedicated microphones for enhanced voice call clarity, these bluetooth headphones provide unparalleled bang & olufsen signature sound. freedom to move: beoplay h9 wireless over-ear headphones can be paired with up to two devices at a time and will remember up to eight. a 10-metre operating range keeps you free to move. 25 hours of music: a single, full charge (taking 2.5 hours) will keep your headphones going for 25 hours, with bluetooth and active noise cancellation switched on, thanks to a bigger, better battery. Power source type: Battery-Powered