Swanson Big 12 S0107-BULK 7-in-1 Speed Square, Aluminum, 12 in L, 12 in W

The Big 12 is seven tools in one, a framing square, try square, miter square, protractor, saw guide, stair gauge and out of square corner angle finder. It's constructed of heavy gauge aluminum alloy and includes the layout bar for use in determining out of square corners. Also included are the Swanson blue book for roof and stairway layout and layout bar with hardware.