A portable version of the earlier versions of the Sea Sled from the 60s, 69, and early 70s, the Underwater Explorer (7354) is a sleek design that was later reused in yellow with a clear green window for the 1975 Jaws of Death set.
The image to the left is the rare 1975-76 boxed version, courtesy of Steve Stovall. Enjoy his work on our sister site 3DSuperJoe.com
Below, John "Toyzilla" Marshall shares three rare polaroids of the original prototype for the set. Note the different shaped nose