The Grandwork™ Hammer Squares stand on a Squaring Platform to indicate the verticality of a grand hammer at strike. The Hammer Square Orginal is a one-piece design, with the inside walls of its legs as references. The Articulated Hammer Square has legs that turn in, employing leg edges as references and bringing them closer to the hammer being gauged. The Extended version helps blind technicians feel both hammer and reference. And the Hammer Square Lite is used where space is tight, as it is when hanging hammers.