I find the above product to be very helpful. I got information about this through a lady in the UK I've done zoom appointments with. She is a respiratory physiologist and works with people with Breathing Pattern Disorder. Always breathe through your nose!
This tool is a diaphragm strengthener. I use it as she directed, twice a day, 30 reps, at 2.0, my goal being 2.5 effortlessly. Overall, I am not cured. But I'm feeling better. Some days, as many as 10-12 with normal breath all day. Best Wishes.