This incredibly rare Seiko, or Seikosha, was made at the very end of WWII. It was designed with a double case in order to provide extra protection in action. Seiko's factories were hit hard during the war and they saw a lot less production, making this a very rare find. The case and strap are all stainless steel. The case measures 30mm, the dial is 22mm, and the lugs are 16mm with an adjustable strap. This watch is running and in excellent condition. We guarantee our watches for up to a year and are happy to service them at wholesale cost forever after that year.