MOST of. This where my concerns have always been with these suits. Not that they dont initially work, but that over time (one to two seasons) their effectiveness goes down dramatically due to the fact that they cant DESORB all of the human odors as well as the other environmental odors encountered and these build up to the point where the garments rendered ineffective. These suits arnt in vacuum sealed bags but instead are hanging on the racks in the stores absorbing all the odors around them for lord knows how long.