Siebe Gorman Vista Vision Mask
The Siebe Gorman Vista Vision Mask featured a large curved triangular window with central speech diaphragm and inlet. There were many applications, including SCUBA, rebreather, and the "Puretha" filter. This example has a corrugated hose that would be connected to a supplied air system, and was made by Siebe Gorman around 1960.
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