The arena Mast MaxLife Thin Strap Open Racer Back Swimsuit will have you swimming like a champion. The Mast MaxLife features our most contemporary open-back cutout for a progressive feminine look with maximum range of motion. arena's most advanced and longest-lasting fabric, 100% Polyester MaxLife suits are designed to deliver maximum comfort, range of motion, and chlorine resistance for the most demanding competitive swimmers, while maintaining superior softness, durability, and performance all season. Swim in supreme comfort and performance in this suit.