This Memorex wireless optical traveler mouse combines today’s latest technology into one convenient mouse! Radio Frequency means cordless operation anywhere…no direct line of sight is needed between the mouse and the receiver.Optical technology ensures precise cursor control and no mouse ball to clean. No mouse ball allows this mouse to operate on most flat surfaces. This Memorex mouse’s three buttons allow users to easily navigate documents as well as the internet. The third button is also a scroll wheel which makes web surfing a snap. This Memorex wireless traveler mouse is even rechargeable using the included USB to DC charging cable and rechargeable batteries!