Unfold the sections of the RIDGID® 6-Foot Fiberglass Outside Reading Rule to take straight-line measurements up to 72 inches or 1828 millimeters. The folding fiberglass ruler is graduated in 1/16-inch increments on one side and tenths of a millimeter on the other and measurements are engraved on the ruler in bold black ink on each edge. Bold red-ink demarcations are engraved for 16-inch stud centering and 10-millimeter increments. The 6-foot ruler has easy-open joints that snap into position as the sections of the ruler are unfolded. The yellow folding ruler is 5/8-inch wide and weighs just 7 ounces. The precision fiberglass construction of the heavy-duty ruler gives it both flexibility and durability.