PTT is being used in the residential and industrial carpet markets because the fibers have a number of traits that make them attractive as carpet products. Since PTT is making its way into the general marketplace, it is expected to begin to appear as forensic evidence in courts of law. Its chemistry and production are described as the authors note that PTT can be easily spun and drawn at high speeds to produce a fine denier product appropriate for sportswear, activewear, and other specialty textiles in addition to carpet products. The analytical properties of PTT are identified and distinguished from the analytical properties of the most common polyester fiber known as poly(ethylene terephthalate) or PET fibers. The chemical structure of PTT is provided and it is noted that PTT has an odd number (three) of methylene units between each of the terephthalates, whereas other similar products such as PET and poly(butylene terephthalate) (PBT) have an even number of methylene units. It is the odd number of methylene units that gives PTT is unique physical and chemical structure, which is more elastic than PBT or PET. Two Web sites are provided for additional information on PTT fibers. Figures, references