PBT Polyester is another more recent addition to the swimsuit fabric world, and is found in both competitive swimwear and fitness swimwear. PBT, or polybutylene terephthalate, has excellent stretch and elasticity; additionally, PBT is also quick-drying and has low-water absorbency.
Current examples of Poly PBT swimwear are YF613, Kiefer?s Aqualast Polyester/PBT blend. It offers stretch, comfort, and last-ability. TYR promotes Durafast boasting a life 20 times longer than traditional swimwear and more recently Durafast Elite. Durafast Elite is chlorine proof, color fast, durable, flexible, comfortable and offers 300+ hours of use. Both suits are blends of Polyester and Polyester PBT. Speedo?s PBT swimwear fabric is known as Endurance Plus and Endurance Lite, and touts chlorine-resistance, color retention, stretchability, comfortable fabric blend of PBT and Polyester.