Bluetooth Chip: JL6973D4 Bluetooth Version: V5.1 Transmission Distance: 10m Drive Unit: 13mm Sensitivity: 118±3db Working Frequency: 2.402GHz-2.480GHz Earphone Battery Capacity: 30mAh Charging Box Capacity: 220mAh Charging Box Charging Time: About 1.5H Music Time: About 4.5H Standby Time: About 60days Input voltage: DC 5V