On the bottom of my mouse there's a US patent number, and searching for it brings me to this lil guy
I have a few computers. This one's a laptop but the display broke so I plugged it into a monitor/mouse/keyboard that I had laying around.
But yes, it's a ball mouse. 20-some years old and it works really well. It has that really nice, stiff, clicky scroll wheel too!
Just saying that cause I tried buying a Razer mouse once. The laser *and* scroll wheel died after a few months.
@MutoShack is your mouse actually a ball mouse?