- Excuse me, sir. Yes, you with the hat.
- Who, me?
- Yes.

7 seconds sound clip from the Back to the Future Part II movie soundboard.

You can hear this line at 01:13:39.549 in the Blu-ray version of the movie.

Quote context

[...]

- Don't worry. The book is on Biff's dashboard. I'll grab it as soon as we get to the school.

- Marty, you must be extremely careful not to run into your other self.

- My other self?

- Yes.

- Remember, your mother is at that exact same dance with you. Yeah.

- Right. This could get heavy, Doc.

- Heavy, heavy.

- Marty, whatever happens, you must not let your other self see you! The consequences could be disastrous.

- Excuse me, sir. Yes, you with the hat.

- Who, me?

- Yes.

- Be a pal and hand me a five-eighths inch wrench out of that toolbox.

- Five-eighths? Don't you mean three-quarters?

- Why, you're right.

- I presume you're conducting some sort of weather experiment.

- That's right. How did you know that?

[...]