I personally use two 3L bottles of water in my bug out bags. One is a standard backpack (holds all the odd and ends), the other is a sweatshirt with the arms and waist area sewn shut. The bottles are in the arms and in the "body" area are my extra clothes. Just throw the arms over the shoulders hanging in front.
I read about this somewhere on the net, but I can't remember where.
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The OGRE
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If we aren't supposed to eat animals,
why are they made out of meat???