This 3-1/2 inch x 18-1/2 inch rectangle ruler features easy-to-read black and white markings printed in 1 inch grids marked in 1/8 inch and 1/4 inch increments. Use the easy-to-read, black numbers (printed on white dots) and the 1/4 inch grip sides to cut whole inches. The 1/4 inch 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 white numbers (printed on black dots) and the 1/2 inch grip sides – to add the 1/2 inch seam allowance. 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! Use the white 45 degree angle to trim half-square triangles in whole inch increments. Use the black 45 degree angle to trim half-square triangles in half inch increments. An additional black 45 degree line is placed so that two angles cross 1/4 inch away from the outside edge. Use these markings to square up flying geese units; squares set on point or mark cross-hatching. The ruler also features a 30degree/60degree angle. White horizontal and vertical lines are printed on the rectangle so the center of the ruler is easily distinguishable. Use these lines to fussy cut stripes and borders. Scan the QR Code printed on the ruler to view a tutorial of these features. Creative Grids Rulers have a MAP (Minimum Advertised Pricing) Policy. Please do not advertise them for less than the suggested retail.