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As a firm believer in O2, I plan my cross country flights (again no passengers) to include a standard cylinder of O2 using a diluter- demand regulator.  My present O2 mask doesn't have a mike but I'm still looking for a reasonably priced mask/mike combination.  Anyone have any thoughts on that topic?

Regards, Bill Hogarty

I use Mountain High's nasal cannula and their Oxygen on Demand regulator for all of my high altitude flights. Mountain High claims that they have tested the nasal cannulae with their Oxygen on Demand regulators up to altitudes of 33,000 feet, if I recall correctly.

When using the cannula, there is absolutely no problem with communications. For emergency purposes only, I think that you might want to consider the cannulae along with the Oxygen on Demand regulator.