Square Squared Half Inch Ruler (9 1/2" by 16") ~from Studio 180 Designs

The Square Squared Half Inch is an all-in-one tool that gives you a window template for accurately cutting the center square, a chart printed right on the ruler for the recommended size to cut the triangles sewn to the four sides of the center square, and a trim down section on the ruler that simplifies the alignment of the ruler to fabric unit and allows everyone to clean up the unit to a precise measurement every time. Ruler Size: 9 ½" x 16" 8 size options from 1 ½" to 8 ½" finished units in 1" increments Step by step illustrated instructions, available to download Instructions for left hand cutting and trimming Fine lines for higher accuracy Free online video for unit construction and tool trim down on Youtube