TWO markers in ONE - The only patented 3 Dimensional dome marker and coin marker. The smooth red marker helps you visualize your ball and line while waiting for your turn to putt. Ideal for tournaments, events, and everyday use. Become a more confident putter and shoot lower scores. Endorsed by US Open Champion and Ryder Cup Captain Jim Furyk. Approved by the R&A and USGA, this revolutionary three-dimensional domed golf ball marker enhances focus on the green. Humans are 3D creatures living in a 3D world, but our eyes capture only two-dimensional images. Depth perception occurs when the brain combines two slightly different images from each eye, creating stereoscopic vision. Because your eyes are spaced apart, each retina receives a unique view. These differences help the brain interpret depth. In putting, accurate vision is essential to identify the aim point, align the putter face, and judge the distance between the ball and the hole. However, peripheral vision can create distractions. The 3D marker helps golfers focus sharply, promoting intense concentration and a "tunnel vision" effect that boosts confidence and improves putting performance.