Use Iron ‘n Fuse Thread by WonderFil Specialty Threads, a 40wt Fusible Vinylon, in your bobbin for appliquè, lining up corners and matching stripes, plaids or patterns, quilt binding, and zippers and more. The heat of an iron will fuse layers of fabric together, holding it in place so you can perfect your project. Then simply pull your top thread out! This fusible thread is sold per 200 yard (183 meter) spool.