The newly designed Lady's Short-Sleeved Rash Guard is made of stretchy nylon material, which adheres to the skin and keeps the body warm. In the water, the high-stretch material is form fitting for maximum flexibility and protects against chaffing from sports equipment, as well as stings from jellyfish and other irritants. All seams are flat-lock stitched for comfort and durability. Rash guards are also great for layering under wetsuits, adding warmth and making putting the suit on easier. The Lycra material delivers SPF40 protection from the sun's UV rays out of the water or while floating on the surface. The rash guard is made of 80% nylon and 20% spandex thick 190 g/m2. The rash guard has a snug fit. It is recommended to follow the size chart to choose the right size.