Golf Ball Alignment Marking Tool is effective to launch a straight line to fill the hole and provide accurate gravity of the ball, helping you to keep the rod stable and correct. It is a great golfing tool for friends, parents, brothers, and families to exercise golf and will be a wonderful gift for Birthdays, Christmas, Family Gatherings, and New Year. Specifications: Product Name: Golf Ball Center of Gravity Marker Material: PP Some Tips: 1. The capacity of the battery must be sufficient to provide power for high-speed rotation. 2. Press and hold the button and wait until the LED green light is fully lit before using it. 3. In the process of using the axis point or the center of the gravity line, you should tap the ball lightly, because the golf ball rotates at high speed on the scriber. If you keep pointing at the ball, it is easy to smudge the line. 4. If the attached marking pen is worn and no longer usable, please use a commercially available oil-based pen (fine-point pen) 5. If the quality of the golf ball is not good, it is easy to jump the ball in the turning groove. Packing List: Golf Ball Spot Marker*1pcs