Bikini‑style foam cups designed for swimwear, active and dance costumes. Provide lightweight coverage that resists water absorption and dries quickly inside lined suits. Shape can be trimmed to fit triangle and scoop tops; sew into place along lining seams. Comfortable under stretch fabrics with enough structure to smooth and support without bulk. Includes two size A cups. Suitable for home and classroom use; keep with core sewing notions for consistent results.