Isomars Professional Set Square-Professional, is a 12 inches / 30cm set square, Thickness: 2.8mm. Made from clear transparent, acrylic plastic. The rate of transparency allows to see the drawing medium below template for easy positioning. Has bevel edge.Contains precise mm/cm graduated scale across the set square, semicircular protractor. Wooden handle. High quality, durable set square for professional applications: technical drawing, art, craft, engineering, architecture. Perfect for school geometry classes.