I bought the 3-liter continuous flow… I bought the 3-liter continuous flow machine less than a month ago, and so far, it's been great. It was well-packaged and is functioning perfectly.

Excellent oxygen concentrator I am currently using the NT-04 oxygen concentrator and it is an excellent machine. It is lightweight, quiet, and offers seven oxygen settings. The price is also very reasonable. In fact, I am using it while typing this review. I recently received my NT-04 and I am extremely satisfied with its performance. It quickly raises my oxygen levels to the level recommended by my doctor for someone my age with asthma. Overall, I am glad I made the decision to purchase the NT-04 as it has proven to be a great solution for my needs.

Ordered an oxygen concentrator it was… Ordered an oxygen concentrator it was dead out of the box. I contacted them and just got run thru the bushes. Illogical questions, nonsense videos, the damn thing won't start. Finally went to Pay-Pal, they said no problem just send it back to China ($410.00) and they would refund my $285.00. I'll talley this one up to experience. What a bunch of confused turkeys. Yes I'll include Pay-Pal. They offered absolutely no protection. Do yourself a favor an deal with Amazon.

Great price and fast shipping I recently received my NT-5 oxygen concentrator along with an extra battery, and I am thrilled with the purchase. Now, I can confidently go shopping by myself without having to rely on anyone else. The price I paid for the device was Great, and I was particularly impressed with the outstanding shipping service. I placed my order on November 2nd, and it arrived promptly on November 8th, despite the long distance from the West coast to the East coast.

The VT-1 fulfills all the claims and… The VT-1 fulfills all the claims and details mentioned on the website. I have conducted tests on both airflow and oxygen concentration percentage, and they align with the stated specifications. Interestingly, I observed that the power consumption is only 50 watts when utilizing a 12-14v battery/car, which is outstanding and surpasses the specified 75 watts. It seems that the 75 watts is in reference to the 120v AC power supply, and there might be some inefficiencies when using a converter/adapter. Furthermore, the unit does indeed meet the 58db sound level that was advertised, approximately equivalent to the volume of regular speech.