Use the horizontal, vertical, and diagonal markings to square up any block – up to a 12-1/2 inch square. Use these lines to center and trim embroidery designs, applique blocks, and even fussy cut T-Shirts for T-Shirt quilts. (Fussy cutting is choosing a specific design in the fabric to showcase in your project.) The drilled holes at 1-1/2 to 11-1/2 inch increments, make it possible to square up, mark and add the seam allowance to any block. To fussy cut, center a fabric design in the 1 – 12 inch printed black solid squares. Mark the fabric through the drilled holes to add the seam allowance to your fussy cut piece - marked with a white dashed line on the ruler. Simply connect the dots and cut to size. The ruler slides easily over the fabric until pressure is applied. Then, our exclusive gripper holds the fabric in place while cutting, eliminating slipping and miss-cuts! Creative Grids Rulers have a MAP (Minimum Advertised Pricing) Policy. Please do not advertise them for less than the suggested retail. .