A Backpack carried around by usually and undergraduate and underage student at WSU filled with a variety of beers and alcohol, but usually just Busch Light. It can be safely assumed that if one is seen after dark with a backpack on, they are lugging a Pullman Backpack to party hop. Not to be confused with a Pullman Balla Bag
"Why does Elijah have a backpack on at this party?"
"So he doesn't have to pay for beer, he's got his Pullman Backpack loaded with beer"
"Man, Ryan has every beer in his Pullman Backpack, lets hope he doesnt get blacked out and punch through a window!"