Ergoguys WUT-13 Blue, Gray 3 Buttons 2 x Wheels USB Wired TrackBall Mouse

It's a trackball, and has two scroll wheels. Fits comfortably in your had and the buttons are easy to use

This is mechanical trackball, not optical. Tracking is terrible, after using for one day it took considerable downward pressure on the ball to scroll up/down and small movements wouldn't register at all. Tried cleaning the rubber contact wheels but...

It's a trackball. Very easy to use both the ball and buttons at the same time

The dual wheels are a bit odd, and without the specific driver, don't do as they are intended (one does the opposite, rather than right-left). It's too old for Windows 7, but will function great otherwise. The placement of the middle and right buttons...

Does everything a trackball should, inexpensive. Has scroll wheels that actually work and don't feel cheap

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