Octopus – Octo (gear)

The Octopus or Octo is another name to designate the alternate air source on a diver regulator set. It comes from the first brand to introduce it Aqualung and named it Octopus. They also introduced the bright yellow color that almost all alternate regulator now has.

DIN – Deutsches Institut für Normung

Cut plans of a DIN connection

DIN or “Deutsches Institut für Normung”, meaning “German institute for standardisation” is a word used to design tank valve and regulator first stage fittings. The other connection used in scuba diving is the A-Clamp or Yoke.

The first modern on demand regulator

Jean-Yves Cousteau and Émile Gagnan patent the first modern on demand regulator valve. After Gagnan was working at Air Liquide on a small demand valve and has been introduced to Cousteau which was looking for a way to regulate the flow from a high pressure cylinder.