Buffalo Sports Pro Series Golf Putting Cup Features: High quality adjustable size putting cup. This plastic golf putting cup can turn any room, office, garage, yard into your personal puttinggreen. Removable smaller inner ring helps improve your putting accuracy. Ring can be removed for standard size hole putting practice. Perfect gift for the avid golfer. Can be used on any surface indoor or outdoor. Smaller hole size with ring is approx 7cm Larger hole without inner ring is approx 9.5cm