Bent Grass Concepts Putt Maker Putting Discs 4-pack - Golf Training Aid - Portable Putting Targets - Same size as golf hole Putt Maker putting discs are like movable golf holes - and are the same diameter Create a personal putting area on the practice greens. Gain visual and audible feedback as your ball rolls over the discs. Perfect for pre-round practice. Used in 2010 Ryder Cup. Fits easily in your golf bag. Plus 17 unique drills on http://bentgrassconcepts.com/files/PuttMaker_Booklet_FINAL.pdf You want to putt on a specific area of the practice green On green where there are none or not enough holes You want to practice at home or office You want to practice a specific type of putt like hills, breaks, or specific distances You want your own personalized putting area