for years I have tried to get equipment from Lincare that I can move myself (oxygen concentrator- invacare platinum xl #5) weighs over 50 lbs. I weigh 57 lbs. portable oxygen I can use outside of my home that fits in case & instructions of what to do when my 2 hrs. of oxygen ( company supplied ) ran out. Don't know how to get more so I save it for emergencies. they (lincare) only service 1xyearly. first time they actually traded units for me they took out an old one that had 2 manuals still in motor and a burnt motor. Don't think oxygen concentrator can work under that polution & over a year ago it was replaced with one new filter. My last tech with lincare finally gave me 4 new filters. My weight constantly plummets tho I have great appetite; my muscles have all deteriorated; my oxygen level dropped from 92 to 85. I'm at wits end these people are killing me; and yet they tell me I'm stuck with them cos of medicare changes & my (non-functioning) equipment is paid for...whoopee!!