Black Friday 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, Light will dim gradually throughout the product's use, so the given battery life is an estimate. Using lower brightness settings will extend battery life. Battery, up to 18 hours of normal use, up to 36 hours in Low Power Mode Battery