The Select-A-Scale twelve-inch architect drafting ruler is a unique and inventive aluminum architect scale with a rotating calibration rod. It is made from high-quality extruded aluminum with ultra-smooth edges. The fixed scale is in 32nds, and the rotating scales are 1/2, 1/4, 1/8, 1/16, 1:1 and 2:1. This scale is an ultra-convenient and functional drafting tool that allows the user to select multiple scales all in one product. This item is a sleeker and more portable version of the more-traditional triangular drafting scale. Available in 7 colors!