Why the countdown?
4 seconds sound clip from the The Green Berets (1968) movie soundboard.
You can hear this line at 00:16:55 in the Blu-ray version of the movie.
Quote context
[...]
- Pack in 10 minutes? Takes me longer than that to get my heart started.
- You pack what Uncle Sam issued and that's all.
- Eight?
- On the way out, everybody grab his gear.
[...]