Momentus IDL Stroke Putting Track Set Set of 2 IDL Putting Tracks. The short track for putts inside 6 foot and the long track for putts over 6 foot. The IDL Stroke Short Track will teach you to putt like the best players in the world. You will notice the ball rolling like it has over-spin on it. Inside, Down the Line is the ideal way to swing the putter if you want the ball to go down the line toward the hole. The IDL two track set is perfect for practicing with the long track at home and short track on the practice green.