Laser Putt putting aid consist of 2 Lasers: GREEN and RED.

It provides visual feedback in the following ways:
The GREEN laser lets you visually confirm that you are lined up perfectly every time and allows you to see exactly where the putter makes contact with the ball. You will clearly see if you hit the ball off the toe or heel as well as the amount of your error.
CALIBRATION: The RED laser shows you the precise apex of your backstroke, letting you putt with repeatable consistency at any distance.

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Laser Putt