Innovative design for competitive swimmers.Worn by world class swimmers, the Fastskin LZR Racer X Openback Kneeskin features targeted compression to streamline the body while still allowing for excellent freedom of movement, making you feel your fastest. Support seams help promote better body positioning and increased muscular awareness, while Speedo’s laser-cut Ab activators™ panels in the suit’s liner increase water sensitivity and prompt you to align yourself correctly. This product has been fully approved by FINA. A combination of 2 unique fabrics offers horizontal stretch resistance, providing intense targeted muscular compression but still allowing for excellent freedom of movement through every stroke Increased linked core stabilizer panels promote a more hydrodynamic shape and better position in the water Laser-cut Ab activators™ panels in the suit’s core liner increase water sensitivity while prompting you to align yourself correctly Maximised support seams improve the linkage of the body’s muscular kinetic chain, promoting better body positioning and increased muscular awareness Precision laser incisions control the stretch of the straps and ensure greater shoulder comfort and fit FINA approved