(1) The technical term for the plastic rings that hold together a six-pack of beer cans.
(2) A serving of beer, i.e., drinking all six beers without removing them from the plastic rings.
(3) "Yoke Challenge": Trying to drink all of the beers in a six-pack as fast as possible without removing them from the plastic rings or dousing yourself in beer; often used as a strategy for Newman's Day.