M171 Logitech Wireless Mouse with virtually no delays or drop outs, you’ll work and play with confidence, consistent wireless connection from distances up to 10-meters (33-feet) away tested to 10 meters, the wireless range may vary slightly based on your computing conditions and environment. Work for up to a year between battery changes. To extend the battery life, use the On/Off switch power off when not in use. Your battery life experience may vary slightly based on your computing conditions and how you use the mouse. The shape of the mouse supports your hand for hours of comfortable use. The ambidextrous shape and the ability to reassign right and left button functions make M171 the ideal mice for the right or left hand