The Men's Performance Endurance+ Jammer is part of Speedo's exclusive Endurance+ collection. This jammer is constructed from Speedo's best-selling training suit fabric, which is constructed from a 50% polyester 50% polyester PBT blend. This fabric is 100% chlorine resistant, offers superior color retention, and features a unique 4-way stretch technology. Size: 32 in Speedo Black.