The triangle ruler set is made of aluminum alloy, with high hardness, strong toughness, anti-rust and anti-corrosion, strong and durable, lightweight and reliable. The geometry kit is laser etched with high-definition scale markings that will not fade, ensuring that every line and number can be read easily and accurately with less eyestrain. This set of metal rulers includes straight ruler, triangle ruler and protractor. Different types of rulers can meet different drawing needs and improve measurement and drawing efficiency. This drawing ruler kit is perfect for professionals and amateurs. It is a must-have measuring and drawing tool for architects, engineers and carpenters, and can also be used for precise measurements in the classroom, office or home. The rounded corners of the size are not easy to hurt your hands.