Dritz Fons and Porter Pyramid Ruler This pyramid ruler is designed to cut equilateral triangles that finish from 1-inch to 6-inch in a snap Features: coordinates with both the Fons and Porter Triangle Ruler and 60-degree Diamond Ruler (not included) his ruler does all the math for you; easy-to-understand directions printed on the ruler and easy-to-understand instructions with photos and ideas for pyramid triangles are enclosed Ruler measures: 6-5/8 by 7-3/4 by 1/8-inch