I used this trackball for years and absolutely loved it!  Once I'd experienced a trackball of this quality I could never be happy  with a traditional mouse again.  Touchpads drive me insane.  So I'm a trackball user for the foreseeable future ... until mind control is a reality?  LOL.

BUT [I wish a larger font were available for BUT!  B B B U U U T T T ! ! !  When the newer, wireless, updated, equally good arguably better M570 is available for 10% as much money, i.e., you can buy TEN M570s for the current price, you'd have to be some kind of moron to buy this for $264.88, its current price.  It's insane.

Maybe you're using a pre-1995 computer and it doesn't have  USB ports?  Even then, these are available right now for less than $40 elsewhere.
I used this trackball for years and absolutely loved it! Once I'd experienced a trackball of this quality I could never be happy  with a traditional mouse again. Touchpads drive me insane. So I'm a trackball user for the foreseeable future... until mind control is a reality? LOL. BUT [I wish a larger font were available for BUT! B B B U U U T T T! ! ! When the newer, wireless, updated, equally good arguably better M570 is available for 10% as much money, i. e., you can buy TEN M570s for the current price, you'd have to be some kind of moron to buy this for $264. 88, its current price. It's insane. Maybe you're using a pre-1995 computer and it doesn't have  USB ports? Even then, these are available right now for less than $40 elsewhere.