The compact M545 is easy to transport and ideal for anyone who prefers a smaller mouse. Quickly navigate through documents and browse your favorite websites in no time with the handy thumb buttons. At just 3 mm in length, our Pico receiver nearly disappears in the USB port. Additionally, you can connect up to six Unifying devices. With the on/off switch, smart energy-saving mode, and battery indicator, you'll hardly think about the fact that this mouse uses a battery at all.