The Putting Alley - Tour Edition Golf Training Aid - Walnut Identifies main putting errors which are putter face angle, swing path and off center impact. Eliminates uncontrolled practice on irregular turf by providing a precise consistent putting surface. Portable - can use anywhere, rain or shine. Easy to use - practice a high number of repetitions in a short period of time without bending over to pick up the ball. Builds putting muscle memory.