PuttOut Devil BallWith its flat edged impact zone, Devil Ball exaggerates your putters face angle for instant, understandable feedback. Up to 90% of a putt's start direction dictated by the face angle delivered. Improving this element of your putting stroke is fundamental to becoming a better putter. With it's flat edged impact zone, Devil Ball exaggerates the face angle of your putter at impact, helping you train to deliver the putter face back to the ball square If