Many people find putting difficult because they want to putt with a straight back and straight through stroke, but can't achieve it. The "Ai-ONE Square 2 Square Putter" is a new model designed to solve those problems. Thanks to features like the shaft being mounted closer to the center of the head and a heavier heel-side weight, the resistance of the center of gravity during the backswing is eliminated, allowing the head to return square to the address position. This characteristic automatically achieves a straight stroke. The head available is the "#7" model, and the Ai-ONE insert and STROKE LAB 90 shaft also greatly contribute to improved performance and stability on the green. I purchased two new putters and am selling this one because I'm using a different putter. It has only been used on a putting mat at home, so I think the condition is good. Please understand that this is a used item before purchasing. Head Material: Stainless Steel / Aluminum Sole Plate / Polycarbonate Insert: Ai-ONE Insert Loft Angle (°): 6.3 Lie Angle (°): 72.0 Length (inches): 34 Sole Weight: Heel approx. 25g, Toe approx. 5g Shaft: STROKE LAB 90 Steel Shaft Grip: Ai-ONE Square 2 Square OS Grip (approx. 66g)