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These bags make a great waterproof liner for backpacks and also add odor protection for bear canisters and food bags while backpacking. Use to do your laundry on the trial!  The are made specifically for the fumigation industry under the Nylofume brand name to protect food and medical items in the home during the fumigation process. Made from a special nylon polymer film.  They measure 20 inches wide by 37 inches long and can be cut down along the length to fit your needs. They are super light, weighing 30 grams each.
The backpack, sleeping bag and other objects other than the liner bag are not included.