Wireless Version : V5.1 Wireless Frequency : 2.402-2.482 MHz Charging Box Capacity : 300 mAh Charging Time Of Charging Box : About 2 Hours Charging Input : DC 5V - 1.0A Built-In Lithium Battery Of Earphone : 3.7V 30 mAh Music Playback : 4.5 Hours (Volume set of 80%) Working Range : 10 m (barrier free )