- High accuracy and quick marking: The thick edge can be used directly with the saw against the square for cross sections or angled cuts with the etched protractor scale, allowing fast and precise marking of cut lines on stringers. - Multifunctional triangle ruler: This triangle ruler functions as a protractor, ruler, saw guide, and triangle knife, as well as a ruler. It is a practical tool for framing, roofing, construction and remodeling projects. - Large size and broad compatibility: 300 x 300 x 430 mm / 12.0 x 12.0 x 17.0 inches in size, suitable for all construction and conversion tasks, and useful for hobbyists, builders, manufacturers and artists. - Dual measurement options and readability: Two scales with metric and imperial dimensions, clear divisions, embossed imperial divisions, and a common rafter conversion table. The squares with triangle ruler are convenient for measuring and reading.