Premium Material: Made of sturdy aluminum alloy after oxidation treatment, this saddle ruler set is durable, distortion-resistant, practical, rust-proof, and corrosion-resistant. Surface: Laser-etched metric graduations and angles on each side of the miter T-rulers are clear and precise, making them convenient and easy to read or make marks when using. Slide to Mark: There is no need to reverse the body when measuring, just slide to mark the right and left 45/90 degree angle. High Accuracy: The square protractor helps you draw perfect horizontal lines while sliding the ruler along the edge of your work. Measuring, correcting, marking in one product. Application: Thick ruler, makes the ruler stable and accurate, perfect for DIY, engineer, carpentry, woodworking and home use.