Type as long as three years between battery changes and use your mouse for up to a year before replacing the battery. The three year battery life prediction is based on approximately two million keystrokes per year in an office environment. Like all batteries, your experience may vary based on the use and computing conditions. Simply plug the tiny USB receiver and enjoy a strong connection with no lag time. Your wireless keyboard and mouse will still be connected up to 10 meters (33 ft) away. While environmental conditions may cause the wireless range to vary slightly, you will always have the connection you need.