The Dynaflex Power Ball is a handheld control ball that athletes can use for grip strengthening. The ball is about the size of a tennis ball and is wound up by a string, once the user pulls the string the ball begins to spin in random directions with force. The user then builds grip strength by holding the ball in one hand and attempting to make controlled and regular motions (in circles) while the ball is trying to escape the user’s grasp. I find this product particularly inspiring because it is so portable and fun to use. I often see the Powerball sitting on my desk and just want to pick it up and do the exercise, the way I am inexplicably drawn to using fidget spinners, and inadvertently find myself improving my grip strength.