Use the straight side of this triple strip ruler to cut 1-1/2; 2-1/2; and 3-1/2 inch strips or use the pre-cuts that are on the market. Sew these strips together to create a 6-1/2 inch wide strip set. Rotate the ruler to cut 120 degree triangles that finish to a height of 6 inch. Continue to rotate the ruler 180 degree to cut additional triangles without wasting fabric. The easy to read black and white markings allow you to cut 2-1/2; 4-1/2 or 6-1/2 inch triangles. A 1/4 inch dashed line is printed on each side of the center vertical line so you can cut 60 degree triangles that include the seam allowance.