SPEEDO Crystal Flash PowerPLUS Flyback Adult PowerPLUS fabric: Brings added power, comfort and fluidity of motion all while reducing drag. Up to 50% lighter than traditional swimwear. Compression technology increase muscle support and elongation for added power. Compression reduces recovery times. Resists pilling; fits perfectly and retains its shape use after use. Our best-selling back features thin strap reinforced with overlap binding for extra durability. Provides excellent support and freedom of motion. Fabric: 79% Nylon/21% Xtra Life LYCRA fiber