Looking for a compact and portable mouse? The Sony VAIO VGPWMS50A Wireless Presentation Mouse is a great choice. With wireless bluetooth and optical tracking, this mouse ensures precision movement. It is compatible with both Windows and Macintosh computers and has a maximum DPI of 800. Its on/off switch makes it easy to operate, and its compact size makes it the perfect travel companion. Can switch between presentation mode or just mouse mode. Mouse is missing Bluetooth dongle. Red optical light on bottom comes on, which can be seen in one of the pictures. Has not been tested, unable to test due to NO USB DONGLE!  BATTERY DOOR COMES LOOSE SOMETIMES AS WELL