I have been using cylinders and big O2 concentrator so long. Recently I have been advised to use a portable Oxygen Concentrator, which can be used even in-flight. Please advice which concentrator would you recommend- Airsep/Philips/etc...?? My current Oxuygen needs are about 3-4 ltrs/min continuos flow.
Where can I buy one from and what is the approx cost??