You're getting 2 sets (4 filters total) of brand new, sealed in plastic bag 3M Scott B series respirator filter pair model 742, part number 10011422. These fit the 3M model 7421 mask. Replace those dirty filters on your respirator with a set of new ones, guaranteed the cheapest on ebay. These are expensive in the stores but you can buy mine at a bargain and have it shipped to your door! Remember, you're getting 4 filters total. Buy multiple quantities for even more savings. These are rated for OV (organic vapor) and would be great for painting, wood working, dusty conditions, remodeling, etc. Protect those lungs, keep harmful things out of them. Take care of yourself and remain healthy for you and your family. Please study the pictures and ask any questions you may have. Thanks for looking and please check out the other items I have for sale.