Dr. Hank Pym, the original Ant-Man, (played by Michael Douglas) is trapped with his daughter in a building that is about to be destroyed. They have no escape until Hank reveals that his tank keychain is more than it appears. They burst through the walls of the building using the keychain because it was actually a real tank that he had shrank earlier. Even the keychain part is expanded. His keychain can be seen several times throughout the movie. And in the early footage of the original Ant-Man that is shown a tank that looks very similar can been seen. One must assume it is the same tank.
