Take a selfie in front of our JAKE Mark V #USSBowfinMuseum

Jake Finds A New Home at Bowfin's Gift Shop

Bowfin Museum

JAKE is our 1961 Mark V Mod 1 standard diving dress, equipment for deep sea diving. 

This artifact received a thorough and much-needed cleaning.  The boot soles and belt weights, made of lead, were deteriorating due to age and exposure to humidity.  Lead carbonate (white lead) can be toxic when it starts to turn to powder, so it was important to remove this material from display. 

The leather harness and boots were cleaned, and special foam was laid under the straps to prevent moisture from getting trapped between the leather and the brass of the helmet.  JHM Productions, a local maker of movie props, helped us to replace all of the lead with a safe, painted foam. 

Cleaning the helmet was a big challenge.  Humidity causes copper to oxidize (turn green, like the Statue of Liberty) and brass, the material used for this helmet, is an alloy of copper and zinc.  If left too long, copper carbonate corrosion can not only discolor an object, but make “pits” by eating away the metal.

After being cleaned, JAKE was transitioned from its original home in the museum to the gift shop display window. Here, thousands of daily visitors can observe this iconic piece of technology. 


The Mark V represents the early 20th century innovation that enabled divers to work at significant depths for the first time. It was used by the U.S. Navy from 1916-1984 and is still used in the commercial industry in environments with especially strong currents. 

The ‘Mod 1’ refers to the large metal chamber attached to the rear of the helmet, which is used to mix helium and oxygen for the diver to breathe. By substituting helium for the nitrogen we usually breathe, the diver can dive deeper, remain clear headed, and return to the surface with less chance of causing the often fatal “bends”.  Jake is displayed without this modification so that he was easier to hang from the ceiling.  This additional chamber adds a lot of weight!

  • It is surmised that the nickname for the suit, JAKE originated from the Navy's first dive instructor, Chief Gunner's Mate Jacob Anderson (1882).

  • JAKE (with all his lead) would have weighed 297lbs. (135kg) on land.  With his current modifications, he weighs about half as much.