18 inch rigid steel rule can be used to measure or as a straight edge SPI's EZ-View rulers features easy-to-read white graduations etched on black nonglare surface 3R Graduations read in 32nds, 64ths, 10ths, and 50ths of an inch Industrial quality precision steel rule 18 inches long x 1-1/8 inch wide x 0.04 inch thick 18 inch rigid steel rule can be used to measure or as a straight edge. SPI's EZ-View rulers features easy-to-read white graduations etched on black nonglare surface. 3R Graduations read in 32nds, 64ths, 10ths, and 50ths of an inch. Industrial quality precision steel rule. 18 inches long x 1-1/8 inch wide x 0.04 inch thick.