The Markit Training Aid is a product that is sprayed on to the face of any golf club including the putter. Once it is sprayed on a golf club a golfer can hit a golf ball and then see exactly where the impact of the ball was on the face of the club. Following are claims made by the maker of Markit directly from their website."Markit is a revolutionary spray which when applied to a clubface will indicate the impact position of the ball, and reveal the clubface position at the moment of impact.""Markit allows golfers to see slight flaws in the clubface position at impact and helps the player to make swing corrections. Proper contact is essential for higher accuracy, longer distance and lower scores.""Markit's unique characteristics allows golfer to see an extremely precise "dimple density pattern" even when used at a clubhead speed of 150 mph. Precise dimple patterns on the clubface will reveal one of the nine basic flight paths of the ball helping golfers to groove their swing, or when learning to shape their shots. Markit can also provide golfers with important feedback when used in putting."