This playing and training aid provides multiple marking options to improve aim, stroke and green reading ability.

Use your preferred marking to establish your aim-line, once confident of the line, you're free to concentrate on stroke and speed. When a good stroke is made, the markings on the ball appear straight with a pure roll. When poorly struck, the markings will show a wobble. When a pure stroke, with proper speed misses the hole, your green read was wrong. Once you've isolated your mistakes, you can make adjustments to improve your green reading skill.

Conforms to USGA rules and is legal to use in competition.