Circa 1949 - The "wrap around" glass port was also used in a 12 bolt closed dress configuration.
Shipped to Fleet Diving Unit Pacific at Esquimalt, BC, Canada, December 1944. Marked 'For Our Mutual Defense' - this Mark V has never been in the water.
This helmet was used in the 1960's by diver Phil Nuytten. Side patch is from removal of He02 demand regulator can and restoration as a straight free-flow helmet.