Polyester: Durable and strong, suitable for heavy-duty fabrics.All the thread is spun polyester machine sewing thread, polyester.Spool thread measures 80/150 m in length. Tensile Strength, Low Lint Thread.Polyester Spun. it will not be fray or break easily. This high-quality thread is perfect for sewing efficiently. Our sewing thread is crafted from a blend of materials, ensuring a strong and durable thread that withstands the rigors of sewing. The composition is chosen to prevent fraying and breakage, providing reliability in every stitch.