Helped me with trying to get the same draw length at different tree shot angles,etc. Best draw length check ever came up with ever in my mind. Hill and others used it. Went with a zwickey no mercy with a straight back to help. I come to the same positive draw every time but keep expanding by pulling my shoulder blades together until I feel the touch and it's gone. Field pts. are tougher and I sometimes cut the back edge with two cuts 3/16ths apart on the back edge and bend it out for a touch point or I just shoot broadheads more. Works for me but maybe not for you.