The SWANSON® Speed® square was first developed by company founder Albert Swanson in 1925. This innovative tool combines 5 tools into 1 - try square, miter square, saw guide, line scriber and protractor. The Speed® square is die cast for durability and accuracy. Made of heavy gauge aerospace aluminum alloy, it is built to last. Black filled gradations stand out against a matte finish for easy reading. The Speed® square includes the Swanson® blue book of rafter length and roof construction and also features markings for using the SWANSON® One-Number® method of rafter layout. The SWANSON® Speed® square is our most popular product and remains the most trusted square of its kind. Look for the Diamond® cutout for genuine SWANSON® products.