I got my Cheaperthandirt catalog last week and i just got around to looking it over. On the cover they have on sale the US Issue gas mask ( OM10 gas mask set). I went to the site and was reading the reviews on it and this one was so funny. Here it is "This mask actually works and works well. My wife has I.B.S. so she is constantly passing gas. When I am fortunate enough to get a warning from her I put the mask on then I can continue to watch Jerry Springer. If this mask can keep the air pollution from her crop dusting from getting me sick it is a winner in my book." That's so funny. Not a bad deal 10 dollars for a used but like new mask with carry bag two new filters. On top of that it comes with the drinking hose and 2 extra lenses and i think it even comes with a water bottle top for the drinking hose. MLT-9104 - OM10 Gas Mask,Filter Carry Bag Protect against Nuclear, Bio, Chemical, Virus if you are stocking up why not add this to your stock. I am sure it will help.