The Johnson RAS-120 is a 12-Inch Alum Rafter Angle Square. Features: * Solid aluminum body with CNC machined edges for greater accuracy and durability * Permanent graduations and numbers are easy to read * Thick edge is useful as a saw guide * Scribe notches starting at 1-3/4" transfer outside increments from pivot point * Low-glare, protective powder coated finish12" body spans wider boards simplifying layout and measurements What"s In the Box: * Johnson RAS-120 12-Inch Alum Rafter Angle Square * Instruction Manual