The Stream Air was a 1950s US Divers regulator. It was one of the first if not the first to have tabs holding on the label and a one piece label side can. It was a good breather, but was replaced by the Mistral. The Mistral was essentially the same regulator, but with a different venturi nozzle. Some Stream Airs were upgraded with the new nozzle and this can be still done today. These new nozzles are available at VDH Venturi Nozzle for a small price. This Stream Air has in fact been upgraded by www.Vintagedoublehose.com complete with a brand new venturi nozzle.