Model:W19 Bluetooth Chip: JL6983D4 Bluetooth Version:V5.1 Transmission Distance:10m Working Frequency:2.402-2.480GHz Battery Capacity:30mAh Charging Box Capacity:220mAh Charging Box Capacity Time:About 1-2H Call Time:About 3H Standby Time:About 30H Input voltage:DC 5V