The Dritz Super Seamer Ruler is a must-have tool for marking seams. This clear ruler is ideal for hemming garments, quilting, and craft sewing. The Super Seam Ruler measures 6-3/4in long by 1/2in wide by 1/4in thick. To mark seams at either 1/4in or 1/2in, simply use the width or the thickness of the ruler. Printed markings indicate measurements as small as 1/8in.