Gigaware Wireless Optical Notebook Mouse 3 buttons - including 360 degrees scroll wheel to easily access and utilize programs and applications Precision optical sensor (on bottom) - provides accurate tracking on most flat surfaces Rubberized grip - for added comfort and better feel Slide-in USB receiver - fits inside the mouse so it can be transported without getting lost Requires: 2 "AAA" batteries (not included); USB compatibility: USB 1.1; Resolution: 1000 DPI; Frame Rate: self adjusting