You know the Tetra Pak brand, and you probably associate it with milk cartons - square boxes topped with funky, fold-out roofs (increasingly replaced by the safer and not-as-fun twist caps. Boo.) Now, what I think of when I hear “tetra pak” - and we all hear it so much, right - is these things that milk came in when I was a wee lad in Croatia:
See, the tetra in Tetra Pak is for tetrahedron, the triangular pyramid shape.
How do you use it, you ask? You slice off a corner, and you lift the container by its seam/spine.
(By the way, not to get too sidetracked, but it wasn’t just plain milk that I drank out of these; there was also buttermilk and kefir and other cultured milks. Everyone, drink more of those! For your health!)
I actually have seen these in America, but only as containers for sour cream to go along with taco salads or pierogies.