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.

So far So far, so good! I've only had the unit for 4 days, but it seems to be working well. A friend of mine wants to order the same NT-03 model, and I might gift one to him for being such a helpful friend. I'll need more information from him to confirm if this is the model he wants.

So happy with my purchase! I am extremely pleased with my purchase. The device works excellently, offering around one hour of usage on a single charge and taking approximately one hour to recharge. It is also lightweight and easy to carry. As a resident of Alberta, Canada, I received my order within nine days, which was quite impressive. To summarize, my experience with the oxygen concentrator has been fantastic, as it arrived promptly and has been functioning exceptionally well.

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 !!

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.