Irwin Aluminum Rafter Square 12"
This professional tool has permanent deep stampings are durable. The aluminum body is rust-proof and weather-resistant. The square has multiple scales: 1/8-, 1/10-, 1/12-, and 1/16-inch. Can be used as a protractor, saw guide and tri and mitre square, and ruler. IRWIN Tools Rafter Square, Aluminum, 12-Inch (1794465)