Pellon SF101 Shape-Flex Fusible Fabric Interfacing, White. 20" x 10 Yards by the Bolt. Pellon SF101 Shape-Flex is an all purpose, woven, one-sided fusible interfacing. It provides crisp support for collars, cuffs, yokes, pockets, facings, and other detail areas of a garment. It can also add body and permanent stability when used as a backing for needlework and punch embroidery. It is intended for light to medium woven and knit fabrics. Color: White. Acid-Free 100% Cotton