Particularly when a strong colorfastness that can survive chlorine are required, polyester embroidery yarns are recommended for embroidery. These strong threads have a high level of resistance to both physical and chemical stresses. A good grade thread will also operate smoothly and loop-free at high speeds on a variety of embroidery machines. Polyester embroidery yarns are particularly well suited for brightly colored fabrics, outdoor clothes, sports wear, swimsuits, kids clothes, workwear, and any other goods that need to be cleaned frequently or exposed to motion, staining hazards, wet environments, or severe weather.