Use the magnetic seam guide to help you stitch straight lines and maintain seam width. Perfect for teaching beginning sewists how to stitch a consistent width seam. The magnetic sticks to the metal throat plate of sewing machine. Fabric edge glides along metal edge to keep stitch line straight. This adaptable seam guide can be used for any width seam and adjusts to any position on throat plate of sewing maching. Extra-strong magnet keeps guide in place. Easy-lift tab helps to release seam guide easily.