This is a set of triple line markers, square line markers, and pens (red and blue). 1. Triple Line Marker This line marker allows you to draw parallel lines on the ball. By drawing three lines on the ball, you can aim the ball more accurately at your target. With a clear direction, you can focus on your target, making it easier to set up your club and concentrate on distance. The ball with many lines drawn on it is used by professional golfer, Pro Katayama. This allows you to check the line with the entire width of the ball, rather than catching it with a thin line. Also, for short putts, you can differentiate your shots based on the line, such as the slice line. It's a simple marker that you just put over the ball and draw lines. 2. Square Line Marker By drawing a blue line on the spherical ball, this ball line marker allows you to accurately impact the putter face, which is a straight line. ① Align the red line straight to the target. ② Align your dominant eye correctly directly above the ball. The blue curve, which is the guideline for the putter face, will appear as a straight line as shown in the third photo. (If you are not looking from directly above, the blue line will not appear straight, as shown in the fourth photo.) This allows you to accurately align the ball and putter face to the target. Even if you align the ball correctly to the target, you cannot make an accurate impact if your eye line is off. Using this, you can hit the ball with the correct impact! This line marker method is also used by player Fujita. If you have any concerns about your putting line, please try it! All items in the first photo will be shipped! Please take this opportunity to try it! * Although it is new and unused, there may be minor scratches from the manufacturing process due to being an overseas product. Please refrain from purchasing if you are looking for perfection. Golf ball marker putt putter improvement goods