content: I toyed around with different trackballs after my wrist began to hurt from a mouse. The microsoft versions, with there quarter inch ball just hurt me more. I tried to buy the legendary Trackman Marble FX, but I could only find a used version that dissapointed me. I bought this as a last resort, and oh my god it is amazing. The ball is huge, great if you have big hands (i'm 6'4). The ring is great for scrolling, and the 4 giant buttons are great as well.pick this up!