This woodworking square protractor is a high-quality measuring tool made of durable aluminum. It is rust-proof, lightweight, and designed for long-term use. The protractor features laser-engraved metric graduations for accurate measurements, making it easy to read up to 112 mm (4.41 inches). It can measure 45-degree or 90-degree angles by simply sliding it, and offers multiple functions including measuring, correcting, and marking, which enhances woodworking efficiency.