SPEEDO Color Blocked Crossback - Endurance Speedo Core Compression features strategically placed mesh compression fabric that trims and slims for the most flattering fit. Engineered from our exclusive, longest lasting and best-selling Endurance+ fabric that: Is 100% chlorine resistant fabric designed to lasts 20 times longer than conventional swimwear fabrics. Has Four-Way Stretch technology providing a body-hugging fit, great shape retention and soft comfort.