My dog Max is a ball-lover.  As soon as we go outside he's dropping a ball at your feet and will give you the death stare, or puppy dog eyes stare.  So when we bought this for Max to avoid the drooly ball and bending over to pick it up, it was perfect!  He absolutely loves this thing.  Once he sees our hand near it, he stands as still as a statue with one leg up, posing - ready to chase that ball.  It works great, gives you an option to throw very far, pop it up, or for short throws.  I recommend the shorter one for a smaller backyard or shorter throw.  Fits regular sized tennis balls.  Don't bother with the ones it comes with, the bounce isn't too great.  Great invention and perfect for any ball loving dog!