Neoprene was developed by a team of scientists back in the 1930s. It has been advanced over the years and now has many applications, such as use in wetsuits worn by deep sea divers. This is due to its excellent insulation properties, protecting the divers from the cold. This benefit is one of the many reasons why these Neoprene Sockettes provide comfort and relief for those suffering sporting injuries or stiffness within the joints of the foot. The Neoprene Therapy Socks are washable (hand wash) & can be used & worn as long as is needed.