Take errors and guesswork out of your next drywall job with this 48 Adjust-A-Square® from Johnson. The T-square s extruded aluminum blade and head are a robust 1/4 thick creating a safer straight edge that prevents your utility knife from slipping while its clear protective anodized finish will provide your tool with corrosion and rust-resistance. It s making it ideal for most drywall work but its head also adjusts to any angle for the unique angle cuts sometimes needed on the job. This T-square was also designed to be easy to use. It features thermal-bonded black that are large and bold for easy reading and the T-square folds flat for easy transportation to and from your jobsite.