Super Magnetic Sewing Machine Seam Gauge. Enables stitching perfectly even seams along straight edges One piece magnet, made of a special unbreakable composition Can be used anywhere on any machine Left or Right of presser foot Adjusts for different seam widths instantly Size : Length 2", Width 7/8", Height 1/4" With needle in down position, simply place this handy magnetic aid to desired width on the metal throat plate bed of sewing machine. Run edge of fabric along seam guide while stitching, and it helps organize the fabric for straighter, more exact, uniform seam lines. Thank you for looking!!