This thing looks almost identical to a no-name trackball I owned like 10 years ago. That thing had a serial connector though, so the circuits are probably different. I remember the big problem with the one I owned was that when the ball got dirty, it tended to want to "jump" off its rollers as you spun it, and would get stuck against the casing ring (and make an annoying sound). So I ended up having to wash the ball and rollers every few weeks. I think the buttons also got unresponsive after a while.