What is the difference between an oxygen concentrator 3L and 5L? How many liters are needed for pulmonary heart disease? Where to buy in Hangzhou?

The difference between 3L and 5L machines is mainly the size of the flow, and the stability of the oxygen concentration, first of all, the general 3L machine flow meter are up to 5, can be adjusted up to 5, but only in the adjusted to 3 within the oxygen concentration is to reach more than 90%, if greater than 3 then the oxygen concentration is to decline, and 5L machine do not have to worry about this, is not changed. Coronary heart disease then generally need high-flow oxygen, it is best to buy 5L machine, Hangzhou Shangtang Road, No. 239, the Oriental mansion on the first floor, the southwest corner of the intersection of Chao Wang Road and Shangtang Road, there is an oxygen concentrator specializing in the sale.