This is the best indoor putting green that I have found. It is a great accessory to your Optishot setup. It is a dual track putting green with 2 different size holes. I use it with my Blast Motion Sensor to work on my putting and have seen great improvement. More information on using Dual Track Putting Green and Blast Motion: http://golfallyear.com/putt-better-5-training-aids/
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