(YMMV) Speed Square on clearance at several Lowe's. Different price at each one. Check the brickseek link for your area.
The Big 12® Speed® Square)s a 12 in. version of the Swanson® Speed® Square with added features for building stairs. This innovative tool combines 7 tools into 1: 1.?ry Square,2. Miter Square,3. Saw guide, 4. Line scriber, 5. Protractor, 6. Out-of-square corner angle finder, and 7. Stair layout Square. The Big 12® Speed®?quare is die-cast for durability and accuracy. Made of heavy-gauge aerospace Aluminum alloy, it is built to last. Black-filled gradations stand out against a matte finish for easy reading and are simple to use with the Swanson® one-number® method of rafter layout. This model includes the Swanson®?lue Book for roof and stairway layout as well as the,ayout bar™&or use in determining out-of-square corners when building stairways.