The stroke follows the shoulders, so aligning them is essential. The Shoulder Mirror for the Eye Line Putting Alignment Mirror (sold one after the other) gives an expanded view of the shoulder alignment. Match your shoulders to the mirror lines and you are prepared for more solid, end-over-end rolls. Not more cut putts. Just slide the shoulder mirror against the ground fringe of the putting mirror. No attachment wanted. Flip the shoulder mirror around for a really perfect arc template, too.It is TOUR TESTED, TEACHER APPROVED & PLAYER PROVEN
