Big Flats Share definition Flag A beer that is somehow cheaper- and crappier than Natty Ice. Displays the words "It's the water that makes it" right on the can. Man, Big Flats actually makes Natty Ice taste GOOD! Big Flats by Wurbles February 22, 2011 0 0 Get merch Get the Big Flats mug. Buy Now — $32.95 See more merch