KENSEN.CO.LTD is a company in Japan. We manufacture thermal underwear to a high quality standard.The name is called a [HIDAMARI]. The [HIDAMARI] means the following things in Japanese.It is healthy and it is comfortable. a good, warm point each day.There are various kinds of [HIDAMARI]. thermal long johns,Socks and supporter, etc.Everything is produced in Japan these.[HIDAMARI] are produced by using the material called TEBIRON(R). What kind of fiber is Teijin TEBIRON(R)?It is said to be one of very few excellent fibertebiron is a synthetic fiber developed by Teijin Limited with its own technologyThis fiber is manufactured and sold for clothing purposes only by two companies in the worldTeijin in Japan and Rhone-Poulenc(Rhovy) in France,which independently developed this type of fiber almost simultaneously with TeijinTebiron&＃39;s superior characteristics have recently recognized as a health-related fiber and been in the spotlight. Tebirons&＃39;s three major important characteristics are: 1.Heat retentionHighest of all fiber -> provides higher heat retention as it gets colder2.dry & warmHighly moisture-permeable -> prevents sticking and evaporative cooling when sweating3.Negative ionGenerated by friction -> produced an effect similar comfort brought by a walk in the woods by surrouding you with negative ions in this way,Tebiron has unique fiber with great advantages over other fibers and is used to produce commodities such as health underwear and supporters.these products are appreciated and used regularly by people who need to be kept warm,such as those with poor circulation or rheumatism.this is why tebiron is recognized as a health-related fiber.Please feel free to inquire of interested one in such a commodity.