The 0.3kg loaf of bread is the lightest and cheapest form of food available to a stalker in Shadow of Chernobyl and Clear Sky. In Call of Pripyat the weight was increased to 0.4kg, making it less economical. Curiously, no one in the Zone seems to know where the bread does come from but it seems safe to eat. At least none of the Stalkers complained about it.
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