The Fairgate Eluxite center finding rulers are made of rigid lightweight, hard aluminum. They are measuring aides for dividing and gauging layouts, printing, spacing, lettering, etc. The rulers are calibrated in 32nds and 16ths of an inch. To find the center of any two- or three-dimensional object, place the rule on the object so that the same measurement appears to both left and right of the zero mark. Zero will indicate the exact center. The rulers are 1¾" wide.