About the Price to write this product, I think is absurd. This product helps me from a smoke-filled building out, you is priceless. If they are unused, it was a waste of money. But on the other hand it is also true, if you want to put this mask all persons of the budget available, and this perhaps in two floors or wings of the house, then you are right in a rich four-digit sum. Because I'm not running up to the bedroom if there is smoke on the ground floor to first of all put on the mask. Another question is, if I ever think in this case of an emergency at this hood and activate it ?! For home use, the mask is suitable rather for those places where you could be trapped locally and the risk of fire is increased. I am thinking of the cabin of a boat, the hobby room. Preposterous a product is not in principle such. You have to look just exactly how it is created and this internalize even after certain period of time and perhaps also look at the course of the same, if the filter has expired. Whether the product delivers what it promises, I can not answer, of course. The idea of processing and materials is at a high level, just as you would expect from Dräger products. They idea of industrial gases and breathing air oxygen equipment. Under the mentioned prefaces a recommendation on my part