Jack Harmen: Stick of gum, right?
Ethan Hunt: No?
Jack Harmen: No. Red light, green light. You come up against a lock you can't pick, you mash them together hasta lasagna, don't get any on ya. You'll have about five seconds. Just don't chew it.
In Prague during their planning stage, Jack gives Ethan what appears to be a stick of chewing gum.