Uhm, where are the buttons? I only see one, where are the other 10?
Actually, you're seeing none
Left and right mouse buttons are just the respective parts of the top being touch-sensitive. The grey nub in the middle is actually a little trackball.
This is one of Apple's more crappy ideas, to be honest. But any ordinary PC mouse works fine with today's Macs, and it will also use all buttons (ie, right click is properties etc).