I have one and used it to help cough up the mucus from a recent viris. My version is a Aerobika. The way it works is when you know I'm to it there is a valve that sends a echo back into the lungs and loosens the mucus and helps get it up. It also has settings to increase the echo of needed. I also use a Incentive Spirometry device 3 times a day to exercise my lungs. This works by slowly inhaling on a mouth piece much like a nebulizer. As you Inhale it moves a disk up a scale and increases the volume of the lungs. Talk to your Dr as see if these would benefit you. God bless and have a great day !