Scroll ring allows you to scroll the web or scroll up and down your Word document screen | Operated with a 40mm ball designed for precise tracking and control | By downloading and using KensingtonWorks, you can customize your own specifications by adjusting your cursor speed, scrolling speed and performing two button function assignments | Optical tracking technology ensures precise and precise cursor operation Easy to operate with just a push of your fingertips to maximize productivity and efficiency | Soft cushioned wrist rest for long hours of PC work can help you work with less pain