First Defense Nasal Screens?

[Jack Parks]

Does anyone have any experience using this product to protect your lungs from dust while working in your shop?  My wife and I saw this on the TV show Shark Tank and we were intrigued.  She suffers from allergies so I ordered some for her to try.  They are expensive, $10 for 7 sets, but if they save your lungs it would be worth it.

http://www.filteryourlife.com/