Worked great - for a few months
Like so many EverGo accessories this worked great for a while - and then started making a terrible noise and stopped working. The warranty was very short so I really had nothing to lose by taking it apart. The fan had come loose inside and a couple of wires had broken. I managed to fix it with a soldering iron.<br /><br />The quality of the accessories for this portable concentrator is terrible. The AC charger stopped working ($165 to replace), two of the batteries have died ($500 to replace) and this charger. At least I was able to fix this myself, but I'm sure many users won't be that adventurous. To have to spend almost $700 to replace electrical parts that were less than 2 years old, after spending $3500 for the concentrator, is just ridiculous.
Rating: 2 stars