yuwell YU500 1.0-5.0l/min Portable Homecare Oxygen Bar Machines Portable Travel Oxygen Concentrator

DOA. Power and + broken and don't work. I guess I'm not the only one, other 1 star reviews had the same exact problem.

If I could give less then a star I would.We like the unit but it stopped working properly. We are currently getting the run around by the manufacturer and Amazon on who handles the warranty exchange. Manufacturer provided an Amazon phone number that goes nowhere. This is a medical issue and the 1 Year manufacturer warranty will be up this week.Amazon and the manufacturer do not honor the warranty!!! Buy Made in USA

Deceptive stats on oxygen production.It produces90% at 1L50% at 2L40% at 3L33% at 4L30% at 5LIt does NOT fit my needs, but it appears to be a awesome little device. That is if those percentages at a given flow rate are within your needs.

Operates very quietly and provides great oxygenflow my wife loves the results this gives her after a bad stroke.

The power button broke at the first use. My father has COPD and need the machine on daily basis. Now I have to return the product and wait for new one to arrrive.

UPDATED 10/5/2018So after more than 14 months on this unit, we've been somewhat satisfied with it. My wife has used this every night without fail and its seems to help although I think there are times she's not getting enough oxygen as she wakes up in the middle of the night having to catch her breath. After more than a year of use, I have the following observations:1) Filter Change Alarm: Probably the most annoying thing about this. It goes off after a number of hours of continual use, don't recall what that is, its not listed in the manual. Most of the time it goes off in the middle of the night beeping loudly for several minutes. It can't be adjusted and you can't proactively or reactively turn it off, you just have to lay their waiting for it to finally quit at which time you're pretty much awake.2) Availability of filters: We had trouble finding the filters at one point, no idea why but we recently were able to obtain more.3) The Cannula that it comes with is very short, doesn't reach to the bed. We found a source (not Amazon) to buy them in bulk at a fair price so we ended up tossing the stock cannula's and went straight to these longer models made in US.4) Difficulty cleaning the unit: For the most part, the unit is sealed however, after over a year of use, lots of dust collected around the vent ports and even around the edges of the top and where the buttons are. We used compressed air and a fine brush to blow off as much as possible but its still not great.5) It may be our imagination and we have no way to measure it but we believe the airflow has diminished since we got it. Not sure if thats a worn compressor issue or what.6) Its definitely not as quiet as advertised. The ad shows ≤40dB, in fact, we measured it recently and got over 68dB (see photo).If you have a vital health-critical need, I don't know that this device would be suitable but for the price and my wife's night-time hypoxia, it is somewhat sufficient but I would like to have more oxygen and a quieter machine with better controls.UPDATED 8/18/2017I am pleased that this addresses my wife's need for the most part. Customer service is what puts this review to 4 stars. We had some issues with the first unit and the company contacted me directly and we were able to work through the issues and we are now satisfied with the outcome and their very helpful support.The only challenge remaining is that there is a filter alert that sounds after about 15 days and only goes off by itself after 5 about minutes until another 15 days, just something we have to deal with. The machine is relatively quiet but it did take us about 2 weeks to get used to the unique sounds it makes but for the most part, its not bad. Similar to what you get with an oscillating fan.Hypoxia is one of the most mis-diagnosed health problems in America and can even contribute to many issues doctors treat with prescriptions or other methods. A doctor friend of ours loaned us an oxygen tank that had just a small amount of oxygen in it to test our theory of nighttime hypoxia and it proved that my wife was having this issue with just a flow of 1.5 lpm. After multiple doctor visits and dead-ends to get an oxygen tank prescription, we bought this machine which helped solve the problem.

great product, great price, fast delivery as powerful as a full size unit

Very pleased with this unit. I had heard the problems with oxygen concentrators are that they are noisy, and run hot. This unit is very quiet, and runs cool. If I had to complain about something, it would be that the LED panel is VERY bright, and lights up the room at night. After I found how cool it ran, I just lay a piece of cardboard over the LEDs.