Triangular metric ruler can be used as protractor, bolster, line marker, saw guide and 3 meter square, framing frame and ruler, ideal for all construction and renovation projects. HIGH PRECISION: Its thick edge can be used directly with the saw against the square for cross or angular cuts using the engraved protractor scale, making it possible to quickly and accurately mark cut lines on currents. The rafter square has ladders for cutting hip and valley beams. Two options: metric and imperial, optional. Has a tuning fork scale from 0 to 90 . Use as a saw guide to measure angles and cuts, ideal for all construction and remodeling projects. The carpenter frame is made of high quality aluminum alloy with matte black finish to prevent glare, corrosion and durability, not easy to break. Suitable for all construction and renovation projects including hobbyists, builders, producers and artists.