Black Friday 12.4 hours of mixed use (4850 + DBMD4 DSP) Battery, 13 hours of mixed use (hands-free Alexa turned ON) with Stylus in idle. Battery, Continuous music playback time: Max. 30 hours(NC ON), Max. 40 hours(NC OFF)Continuous communication time: Max. 24 hours(NC ON), Max. 28 hours(NC OFF) Battery