Near the beginning, Montag puts on the fireproof clothing to use the flamethrower. It's really footage of him later taking off the same equipment played in reverse.
In keeping with the theme of no books this movie has no text visible anywhere except the opening theatrical logo. Even the credits are not shown on the screen. The only symbols shown in the movie are numbers, such as the 451 medallions on the fire crews and their equipment. Signs can occasionally be seen in the background.