Black, flexible sew‑in boning that delivers shape and support without bulk. The polypropylene core with a smooth nylon cover feeds easily through channels and handles curves cleanly. Perfect for strapless dresses, bodices, swimwear, lingerie, costumes and structured accessories. Trim to size and finish ends to protect fabric. Washable; press lightly through a cloth. For best results, test on a fabric scrap to confirm placement, stitch choice and care settings before finishing.