Omnigrid Square Quilting & Sewing Ruler, 15" x 15" Michaels Omnigrid Square Quilting Ruler Value Pack : Target Omnigrid Square 8 1 2'' Omnigrid 2.5 Square Ruler The Quilting Shed Omnigrid Triangle Ruler 8in. Creative Grid Rulers slide easily over the fabric until pressure is applied. The grip coating holds the fabric in place while cutting, eliminating slipping and miss cuts! A 45 degree angle is printed in black and is used to trim half square triangles to size. White horizontal and vertical lines are printed on the square so the centre of the ruler is easily distinguishable. Use these lines to square up blocks based on four patches or embroidered and appliqued blocks.