Anodized aluminum for maximum durability, light weight, and corrosion resistance. 1/8 In. graduations on face and back. Provides reference conversion tables such as new lumber scale, decimal equivalent table, metric conversion table, formula for squaring a foundation, 45, 60 and 30 Degree angle markings, volume and area formulas, wood screw gauge table, nail sizes (common and finish), quantity per pound and depth scale. Embossed graduations and figures for easy reading.