Operating range: 15m(MAX), without signal disturbance and no direction limit Frequency range: 2.403GHZ ~ 2.480GHZ Operational voltage: 3.3V Charge Voltage: 4.4V ~ 5.25V Modulation: GFSK Channel: 78 channels TX Power: Less than +5dBm Transmission rate: 1M bit/sec Frequency tolerance: +/-30ppm Power consumption: 55mA(on), 1mA(sleep) Battery Type: 2 x AAA bateries (not included) Item size: 145mm * 100mm * 20mm HID compatible device Terminal with USB port Windows Vista, Windows CE, Windows 7, Windows 8, Windows 10 Windows 2000, Windows XP Linux (Debian-3.1, Redhat-9.0, Ubuntu-8.10, Fedora-7.0 tested) Android OS (With standard USB interface) Package Content: 1 x Wireless keyboard 1 x Wireless receiver (in wireless keyboard) 1 x User manual