Alumicolor 12" solid aluminum architect's scale ruler is durable, high-quality, made from extruded aluminum. Photo anodizing process makes the calibrations a part of the aluminum, providing a smooth, tick-free finish and markings that are resistant to cleaners and solvents. Silver 12" triangular architect scale with color-coded furrows (red, green, blue) to easily identify the graduations. Standard architectural graduations of 16, 3/32, 3/16, 1/8, 1/4, 1/2, 1, 3/8, 3/4, 1 1/2, 3 inches to the foot. Executive weight and feel; widely used by drafting professionals.