Exactly what does the World's Softest Sock feel like. Ultra-soft acrylic and nylon fibers create the sock recognized as the World's Softest Sock. The fibers wick moisture away from foot, keeping it dry and comfortable. Nylon adds stretch for an ideal fit and long-lasting durability. A fully cushioned sole absorbs shock and maintains all day comfort. The contoured heel and toe pockets create an anatomical fit that prevents friction and bunching. Low profile toe seam. Reinforced heel and toes offer durability in high stress areas. Cushioned tops stay up without binding or sagging.