BRAND NEW WIRELESS & ALSO WEIGHTLESS ECO 2.0 SERIES HEADPHONE WITH 20 HOURS BACKUP. BATTERY Capacity: 200mAH, BT Version: 5.0, Distance: 10Meters, Playtime: 20 Hours, Charging time: 1.5-2Hours, Frequency Response: 20Hz-20000kHz, Standby Time: 60H.