A4Tech GK-520D. Device interface: RF Wireless, Keyboard layout: QWERTY. Frequency band: 2.4 GHz, Wireless range: 10 m. Keyboard dimensions (WxDxH): 166 x 321 x 25.4 mm, Mouse dimensions (WxDxH): 55.6 x 97 x 36.5 mm. Battery type: AAA, Current consumption: 8 mA. Compatible operating systems: Windows 2000/XP/Vista