... . 2.4GHz wireless USB receiver, the effective reception range of 10 meters, built-in lithium-ion batteries support 2,000 hours ... time of up to 2000 hours. 5, the working range: 10 meters. 6, the transmit power: 0dBm. 7, operating voltage: 3 ... continuous use. 9, the charging voltage :4.2-5 .0 V. 10, the charge current: <300mA. 11, lithium-ion rechargeable battery. 12 ...