For patchwork projects with seam allowances of 3 mm (1/8″) or 6 mm (1/4″) 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 Patchwork Foot with Guide #57 differs from Patchwork Foot #37 only in that it has a built-in seam guide along the right edge of the foot. It is therefore particularly suitable for patchwork projects with 1/4″ (6mm) or 1/8″ (3mm) seam allowances.