Size: 12" X 12"Material: Aluminum AlloyGraduations: 1/4"Heavy Duty Aluminum Alloy Construction For Durability And LongevityFunctions As A Framing Square, Try Square, Miter Square, Protractor, Line Scriber, Saw Guide, Stair Gauge And Out-Of-Square Corner Angle FinderBlack Graduations For Easier Reading With Matte Finish To Prevent GlareIncludes Swanson Blue Book Of Rafter Length. Roof Construction And Stairway Layout, Layout Bar And HardwareBlue Book Also Includes Tables, Formulas And Diagrams