The Swiss Tech 7-inch Rafter Square features a solid aluminum body with easy-to-read numbers. Square has continuous scribe notches. The square is easy to read and easy to use. This rafter square is designed to make easy rafter pitch or slope calculations. It is handy as a protractor, combination square and saw guide. Durable aluminum construction has cast markings that will not rub off and a matte finish for reduced glare. Markings include inch, Hip-Val and protractor scales. The rafter layout square is made from a durable anodized aluminum that is more durable than diecast and will not rust or corrode after exposure to the harsh job site elements. The rafter square features conversion tables for common applications.