The file
"Keep the hot side hot and the cool side cool." The McDLT's whole idea was its box: a double-wide styrofoam clamshell that kept the bun and meat on one side and the lettuce and tomato on the other until you put them together yourself. Jason Alexander sang about it in the commercial.
It was a good burger with terrible timing. By 1990 foam packaging was the symbol of fast-food waste, McDonald's phased it out, and the McDLT couldn't exist without it. The Big N' Tasty and others tried to fill the slot; none had the box.
Sources: Wikipedia — McDLT
