Genius SlimStar i820. Device interface: RF Wireless. Movement resolution: 1600 DPI, Movement detection technology: Optical. Frequency band: 2.4 GHz, Wireless range: 10 m. Keyboard dimensions (WxDxH): 458 x 142 x 26 mm, Keyboard weight: 730 g, Mouse dimensions (WxDxH): 95 x 45 x 30 mm. Battery type: AAA