2.4GHz radio frequency wireless technology works up to 30ft; Ergonomic design with split key zones & gently sloped shape encourages natural position of hands, wrists & forearm in maximum comfort for long use; 20 built-in hotkeys for controlling multimedia tools & browsing Internet; Membrane key switches provide better tactile response & quieter typing experience & last up to 5 million keystrokes; Switch at the top of mouse allows quick & easy switching (800dpi/1200dpi/1600dpi); 2 convenient side Internet forward & back buttons for quick Internet navigation; Battery-saving on/off power switch on the base of device extends battery life;