ALWAYS CHECK THE SIZE CHART (IN IMAGE SECTION ABOVE). SIZES PROVIDED ARE UK SIZES, BE SURE TO MEASURE AND CHECK THE SIZE CHART BEFORE ORDERING. The Rival 2.0 open-back kneeskin in black is FINIS' elite level racing suit designed using for performance. The performance suit is made as on of Finis' finest, combining three main principles is what makes this suit the essential to have in the water, designed with the main principles:? Flexible Hip Panels - The Rival 2.0 kneeskin uses single-layered panels on the inner thighs, with this design is increases range-of-movement ensuring the swimmer has the best movement within the water during all four strokes.? Sheild-Tech Proprietary Fabric Innovation -?Rival 2.0 features a new, proprietary fabric called Shield-Tech??. Developed using a unique weave-method, Shield-Tech?? provides the suit with a perfect combination of durability and flexibility. The fabric's surface retains a very small amount of water, creating a shield-like effect and reducing friction. Complete Compression System - The Kneeskin has complete compression over the whole suit, in the core there are many different aspects to help with the compression and the performance. The vertical chest seam and the fabric cutout provides compression and prvets air pockets all while allowing the suit to breath and adding room with range-of-motion. Within the complete compression system the oblique and lower-abdomen seams provide compression throughout your core, while in the thighs seams run parallel down the back to increase the compression in the legs. Being double layered throughout the back of the suit for a more compressive fit that lifts the his to the surface.? The Rival 2.0 is packed with all unique performance-enhancing features, all designed to ensure you perform your best on race day.? The Finis Rival 2.0 is FINA approved for competition use.? Features-Two-way stretch fabric?-Abdominal system?-Full compression in all areas of the suit?-Seams placed in adjacent areas to complement and strengthen the fabrics and compression-Elite fit with a balamce between compression, support and flexibility