IRWIN Tools Framing Square, Hi-Contrast Aluminum, 16-Inch by 24-Inch (1794447) This professional tool has permanent deep stampings are durable. The aluminum body is rust-proof and lightweight The square has multiple scales: 1/8-, 1/10-, 1/12-, and 1/16-inch Features rafter tables, brace and octagon scales and Essex board measure. Can be used as a protractor, saw guide, and ruler Yellow markings on blue background are easiest to read