This set includes 3 pieces of ball alignment tools, each containing a ball marker with an alignment line and a matching marker pen. Made of durable plastic material, it is lightweight and portable to carry around golf courses. It helps you draw a clear straight line on your golf ball easily, which can effectively improve your putting accuracy and consistency. It is perfect for both daily golf training and practice, and suitable for golf beginners and experienced players to use during on-course play or off-course practice.