That is a pig tail screw. See, pigs are born with long tails. This is undesirable, as it will tangle with other pigs, which will lead to them communicating with each other to untangle. This will lead to a great pig uprising. That will lead to no bacon. No one wants that. So, the farmers take this curler and curl the pig's tails so that they are no longer a danger of tangling with others.
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