Avoid this company
Find a more reputable company to purchase your oxygen machine from. The only machine that the sales rep recommended stopped working within a few months of very light use. Instead of replacing it, I had to send it off for three to five weeks with no replacement or interim unit offered and they recommended instead that I BUY ANOTHER UNIT FROM THEM! They admitted that the one they sold me has a history of malfunction issues and that I could buy another one that is less prone to breaking down. Come to find out, buying from other dealers or straight from the manufacturer will get you a better warranty and a better guarantee that you won't be stranded without an oxygen machine. Avoid this company!