The Yokahama Diving Company has been in business for well over 100 years possibly as long as 120 years . The company, from Yokahama in Japan used designs similar to the American and English helmets. The Yokahama Diving Apparatus Company is sadly no longer in business.

Air helmets

An early Air helmet of the 12 bolt design with the characteristic criss-cross side window guards. Notice also the large front window.
Unlike many Far-eastern helmets this helmet has a spitcock.
The rear view of the helmet shows the air inlet with non-return valve and also a telephone gooseneck.
This is a much more substantial fitting than is normally found on helmets from Japan and the Far-east. There is also a spring loaded locking device
A close up view of the crown of the helmet shows it is of a hand beaten construction and the zig-zag interlocking pattern can be plainly seen through the patina.
This signifies it is not machine turned and is an early helmet dating to around the1930s. The helmet is very robust and the workmanship is to a very high standard. . This helmet was purchased in Okinawa Japan.

Photo courtesy of RJ Timmerman

Yokohama Sensui ( Yokohama Diving) 12 bolt helmet made in Hiroshima in the late 1930s or early 1940s

Photo courtesy of Richard Donofrio

There are a number of similarities between the English and American helmet features and those of the Yokohama helmets.
Here is another early helmet.

It has several KirbyMorgan features like a large front window, the external telephone booth on top and the safety pin at the back of the bonnet. It also has "Asian" features like a small breastplate and the guarded side windows. This is very nice helmet in working condition. Most of the tinning is still in tact and a part of the communication wire is still present.

In the early 1960-ies Bob Kirby and Bev Morgan teamed up and started producing KirbyMorgan helmets. You can see them in the American helmet gallery. Soon they got in touch with the Yokohama company. They found out that the Japanese could produce their helmet in the same quality for less money. Thus, a partnership was created. For this reason you will find Yokohama commercial helmets that look exactly like the KirbyMorgan commercial helmet.

Nice 12 bolt helmet in used condition. The owner mounted a little torch to the side. Below you see the nametag of this beauty, that used to be black when the hat left the factory.

Side view of the air helmet

A 4 light Air hat with a conventional screw-in front face port but with Plexiglass side and top ports. There are 2 lashing eyes located on the front brales and a spitcock and adjustable air exaust valve. There is a banana exaust vent showing the influence of the American design taken from the Mark V helmet. The locking device is located at the rear of the helmet.

Photo by Diving Heritage

Helium helmets

A very nice tinned Yokohama helium helmet. Divers went down on a mixture of helium and oxygen. 
The cannister on the back contained the CO2 absorbent material. Visit the "Going Deep" section to learn more about mixed gas diving.

Side view of the tinnend helium helmet. This one looks in mint condition, with not a scratch on the windows.
The Yokohama Helium Helmet has four Plexiglas windows, the front window screws in for the diver's comfort.
To the rear of the helmet there is a scubapro regulator which was designed to provide
a constant blowing pressure to the venturi for circulation through the scrubber.

Yokohama is no longer in business.