BERNINA Patchwork foot with guide #57 sews precise straight lines and is ideally suited for sewing and patchwork projects. For patchwork projects with seam allowances of 3 mm (1/8 in.) or 6 mm (1/4 in.); Three notches on the side for precise guidance; the guide allows perfectly straight lines to be sewn. For 5.5 mm and 9 mm machines.