- Hey, Sefton. What's the big idea? Take that telescope out of here.
- Says who? Says me.

6 seconds sound clip from the Stalag 17 movie soundboard.

You can hear this line at 00:42:05.057 in the Blu-ray version of the movie.

Quote context

[...]

- You couldn't catch much through that steam, but believe you me, after two years in that camp just the idea of what was behind that window sure spruced up your voltage.

- Let's go. Twenty seconds to a customer.

- Hey, Sefton, what's snarling up the traffic?

- By the time we get to look, they'll be old hags.

- Simmer down, boys, simmer down. There'll be a second show when they put the next batch through.

- Hey, Sefton. What's the big idea? Take that telescope out of here.

- Says who? Says me.

- You take it out. Only you're gonna have a riot on your hands.

- Every time the men get Red Cross packages, you have to think up some angle to rob 'em.

- The Krauts find that gadget, they'll throw us all in the boob.

- They know about that gadget. I'd worry more about that radio.

[...]