Designed for general carpentry use, Adjust-A-Square is ideal for marking cut lines on sheets of plywood, OSB, drywall, and other board materials. Extruded aluminum 1/4 In. thick blade and head offer durability. Clear protective anodized finish will not rust or corrode. Screened, thermal-bonded, bold black 1/8 In. and 1/16 In. graduations are large and easy-to-read. Head adjusts to any angle. Precision-machined head and blade lock together for a perfect 90 Degree angle. Folds flat for easy transportation.