This "aqua lung" was made under contract in Japan by Kawasaki Nihon.  It is very similar to the US version save for a few minor details.  The Kawasaki is metric, came with seamless hoses, different clamps, and most interesting is the lead seal on the can halves.  I would only guess that after a tech would do a rebuild on this regulator he was required to wire in a new seal showing the regulator was rebuilt and untampered with.  With the aid of www.VINTAGEDOUBLEHOSE.com  I hope to have this regulator in the water for the upcoming Sand Dog.