Make diamonds and triangles quickly. Perfect for tube piecing 1/2 square triangles as well. The ruler measures 23in x 6.5in. Cutting area is 3in x 23in. Since the ruler is slotted,it allows you to make cuts without picking up and moving your ruler. Numbers are on both sides, allowing you to flip the ruler over and easily cut left handed, or do secondary cuts to make different shapes (long triangles trapezoids, etc.) The Gruuvy™ Let's Jam ruler is made in the USA from clear, flexible material. Mean for use with a 45MM or 60MM rotary cutter.