Kensington Expert Trackball Mouse (K64325), Black Silver, 5"W x 5-3/4"D x 2-1/2"H
The Expert Mouse Wired Trackball is the ultimate productivity enhancer that makes working at the desk quicker, more accurate and extremely comfortable for your hand and wrist. Featuring DiamondEye technology, the trackball uses optical tracking to precisely follow small flecks embedded in the large 55mm ball to provide smooth, accurate cursor control. The four buttons are customizable using our highly intuitive KensingtonWorks software, while our award winning Scroll Ring lets you quickly scan up and down web pages and large documents. Add it all up and you get exceptional comfort and ease-of-use that has set the industry standard for more than 20 years.

Kensington Orbit Trackball Mouse with Scroll Ring (K75327WW)
Kensington trackball legacy continues with the latest addition, the orbit trackball with scroll Ring — space gray ball, designed to complement your desktop and office aesthetic. It includes the features that make the award-winning orbit trackball with scroll Ring The popular choice of professionals everywhere for everyday precision, productivity, and comfort.