The Siebe Gorman Savox was an industrial and
mines rescue oxygen rebreather
A rebreather is a breathing apparatus that absorbs the carbon dioxide of a user's breathing, exhaled breath to permit the rebreathing (recycling) of the substantially unused oxygen content, and unused inert content when present, of each breath. ...
breathing set with a use duration of 45 minutes. It was worn in front of the body. It had no hard casing.
External links
*http://www.healeyhero.co.uk/rescue/glossary/aerorlox.htm
Rebreathers
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