L'il Donnie jokes:

Li'l Donnie goes into a store and sees a shiny object.
He asks the clerk, "What is that shiny object?"
The clerk replies, "That is a thermos flask."
Li'l Donnie then asks, "What does it do?"
The clerk responds, "It keeps hot things hot and it keeps cold things cold."
Li'l Donnie says, "I'll take it!"
The next day, he walks into work with his new thermos.
His boss sees him and asks, "Whacha' got there?"
He said, "It's a thermos flask. It keeps hot things hot and cold things cold."
The boss said, "Wow, what do you have in it?"
The moron replies, "Two cups of coffee and a coke."