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.

I purchased one of their units and O boy what a ripoff I purchased one of their units, after I received it I tried it and realized it was not going to work for me. Since the unit had a 30 day return policy for a full refund, I started trying to call their listed customer service number and found out later in an email that their phone number wasn't working! Then after 9 emails they finally gave me a Rma number and the shipping address that was in China I attached a label and took to UPS where I was told it would cost 400 to 500 dollars to ship it to China which exceeded the purchase price of 351.10. So it's a ripoff if you ever need to return it for credit or service!! What a rip-off!!! BUYERS BEWARE !!

Thank you for resolving the delivery… Thank you for resolving the delivery issue with the portable concentrator battery. After the first one got lost in transit, you promptly sent a replacement, which works perfectly. I would recommend your company to anyone in need of oxygen therapy.

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.

Recieved Oxygen concentrator 7 days… Recieved Oxygen concentrator 7 days from order. Machine operates great. I have used it for nearly 48 hours without incident. Remote control unit isn't operating but have not yet contacted company. Pleased with concentrator plan on using on vacation travel, it's about 1/3 the size and the weight of my medical supplied unit.