Beijing North Star Yaao Scitech Co., Ltd. is a Hi-tech share-holding enterprise, which is specialized in developing and manufacturing oxygen concentrators.Yaao developed and produced the first set oxygen concentrator in 1992, and is also the first top enterprise that produces medium and small typed medical molecular sieve oxygen concentrators in China. Yaao occupies more than 4000 square meters' production area; the present production output is 25,000 units per year. At present, we are able to produce hundreds of types of oxygen concentrators with different outlet and functions. We...