Sew-In Hair Canvas Fabric Interfacing, Off-White 21" x 10 Yards by the Bolt. HC110 Sew-in Hair Canvas Interfacing is an excellent tailoring product. It is a woven interfacing that is suitable for garment construction where crisp detail or firm control is desired. Use with medium to heavyweight fabric. Do not use in triacetate, seersucker, lace or rainwear fabric. Natural / Off-White 47 percent cotton viscose/27 percent cotton/11 percent polyester/11 percent horsehair/4 percent wool 21" width 10 yard bolt By the Bolt Woven sew-in interfacing for traditional tailoring Use with medium to heavyweight fabric Sewing machine safe Dry clean only with ironing on low, medium permanent-press setting