I have this and love it for same reasons Tiffa says. You can really zero in on certain areas, (if you can reach). I had a broken shoulder and could not use the vest so i got this and it was a godsend… plus my husband or PT at hospital can use it on me… great to travel with, (not as cumbersome as the vest)… Not sure about the collapsed lung part, but you can adjust pressure/speed for sensitive areas… there is a video I will try to find and send you. They were great about working with us for insurance so I can help you with that maybe if you need
