With an excellent patina, this 12 bolt dive helmet is a great example of hard hat dive gear that was used and modified over many years. Though the maker's plaque is missing we were able to identify this helmet as a Yokohama helmet with significant modifications. DESCO concurred with this as well. Modifications are not unusual, particularly in helmets like this one that saw heavy use. As parts wore out or new innovations came along helmets would be modified to extend their useful life.
The side windows with crossed covers and smaller breastplate along with the large front window are consistent with other examples of Yokohama helmets. It appears that the spitcock valve is from another Japanese maker, TOA Diving Equipment Ltd.
The Yokohama Diving Apparatus Company was founded in 1860. Though the company is no longer in business it made dive gear for more than 120 years.
