The 18 Inch Aluminum Ruler by Mayes will always measure up. Sturdy and light, straight and accurate, it's ideal for a wide range of hobbies and professional jobs. It is made of 0.090 inch thick extruded-aluminum with a brushed finish and features easy-to-read Thermo-bonded graduations in 1/8" and 1/16" scale. From the Manufacturer Mayes' 18-inch Straight-Edge Rule is made of sturdy, extruded, lightweight aluminum with thermobonded, embossed graduations. No matter what the job is, Mayes helps make sure it's done on the level. Mayes is committed to making the best tools for the skilled professional tradesman who demands the best.