Creative Grids Quilt Ruler 16-1/2in Square features easy-to-read black and white markings printed in 1" grids marked in 1/8" and 1/4" increments. Use the easy-to-read, black numbers (printed in white dots) and the 1/4" grip sides to cut whole inches. The 1/4" dashed lines printed on two adjoining sides aid in trimming seam allowances. Use the patented Turn-A-Round feature designated by the easy to read, numerical numbers (printed on black dots) and the 1/2" grip sides - to add the 1/2" seam allowance. 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 of the ruler is easily distinguishable. Use these lines to square up blocks based on four-patches or embroidered and applique blocks. The ruler slides easily over the fabric until pressure is applied. Then, our exclusive holds the fabrics in place while cutting, eliminating slipping and miss-cuts! Creative Grids products are made in the USA.