This is another one of these handy, lo-tech devices that is very good at accomplishing what it promises. It’s a regular ball simply one half black and one half white. Why is this effective? Because when you strike it properly, the ball shows you by its wobble or its steadiness how squarely you struck it. You get immediate visual feedback. You don’t even need a hole to aim at. You just line the ball up where the two sides are equal when you look down at it. You can retreat to a part of the practice green where no one is and practice putts of varying lengths to your heart’s content. When the ball shows it’s rolling true, you know you’re getting somewhere, whether you’re using the pendulum style or the inside-to- square-to-inside method. Just start making adjustments until you consistently see the ball without the wobble that appears when one side of the ball overshadows the other.
It comes with three balls to a sleeve and nothing else. You can use it for chipping practice as well, but I haven’t quite got the hang of it for that purpose. It’s inexpensive. And there is a video on their website at eyelinegolf.com.
It’s not the be-all, end-all of putting instruction, but it’s helpful to know how true and solid you are striking your putts. I recommend it.
Recently, they’ve added a red T to the ball between the black and white side, but I haven’t the slightest idea why!