OMS Evoque OctoEvoque Octo The AirStream Evoque Octopus shares all the same features of the Primary Evoque. Some of the unique features of the Evoque second stage are the exhaust deflector with a door that opens to give access to the flapper valve. The exhaust deflector is also designed to work in conjunction the OMS Tattoo Mask, allowing the exhaled bubbles to route up behind the sides of the mask. The Predive Dive switch keeps the Evoque from free flowing when the