I traded some stuff I never use for a medical oxygen concentrator not too long ago and I use it for welding. An oxygen welding hose screws right onto the unit and all I have to do is plug the machine in, push a button to turn it on, and adjust the lpm flow of oxygen. My unit is an integra and does 5lpm at 93% purity or 10lpm at 90% purity. Even at 10lpm, 90% pure oxygen is more than sufficient for welding. Unfortunately, I cannot really cut with the unit because it doesn't have the pressure required to do so. I've been trying to find a unit on letgo or offerup or facebook with a homefill system that I can adapt to fill high pressure cylinders. The only people out there online that I have found so far with any knowledge on this are glassblowers for some reason. I haven't met any welders yet that know anything about this. I feel that it is much safer to weld with the hose attached directly to the concentrator unit because if there is a flashback in the oxygen line, it doesn't lead back to a pressurized cylinder that can explode. Anyways, I'd like to hear from others on this subject. Does anybody else have any experience with this? What do you know about it?