53% Polyester 47% (Pbt) | Lining: 50% Recycled Polyester 50% Polyester NIKE HYDRASTRONG fabric provides long-lasting durability, swim after swim The NIKE RACERBACK has narrow straps for medium support. Moderate back coverage Full Bottom Coverage High-leg Height sits above hips allowing for a wider range of movement LINED for better fit and security FLAT SEAMS for reduced chafing Heat transfer Swoosh