Patchwork Foot with Guide #57D 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. Other precision sewing techniques requiring a perfectly straight seam also benefit from the use of Patchwork Foot with Guide #57D. Here, the edge guide is placed directly against the fabric edge or seam line to yield straight spacings and lines when sewing.