Vests are placed on the upper torso and the machine that comes with it inflates the vest and then the vest will be set for time of use, speed of vest pumping and deflating and pumping, and the pressure to be applied while it is pumping in hopes of reaching the lung areas and helping to move the mucus such that it will come up to get it out.
As Sue and others have mentioned, some do well with the vest and others have problems with the vest due to it possibly affecting certain organs and soft bones etc. Again, due to our body structure and health it may or may not be an answer for some people.
NJH recommends it and others not so much. So again all different philosophies from doctors and professionals. If one has the opportunity to try it one should consider it.
If prescribed by a doctor and Medicare approves you to have it, you have a window to decide if it is working for you and if not you can return it within that window and the company should reimburse Medicare etc.
Always good to ask questions of the company to know the rules and regulations.
I decided to return mine due to my experience of having pain develop on my left front side after having used it for a while.
Barbara