A putting training aid comprises a short-putt module, a long-putt module, and a third putting module. The latch nut comprises an outer nut body with two arms for operating the catch and the bolt, respectively, as well as two hubs each connected with a square section of the outer and the inner door handle and coaxially and rotatably positioned parallel to each other inside the outer nut body. The current position is added to a historical table of previous position determinations and a normalized center position is calculated from the current position and previous position determinations.