- What's the second reason?
- A pip!

4 seconds sound clip from the The Thin Man (1936) classic radio play.

You can hear this line at 00:33:22 in the radio play.

Quote context

[...]

- This is Al Nunheim again. You know, I called you last night.

- Hey listen, are you still interested in that proposition? You are, huh? All right then.

- Now, here's the dope and get this straight, the man who killed Julia Wolf is... (Gunshot)

- What's this Guild? You think Wynant killed Julia Wolf and Nunheim?

- Right.

- Why?

- Two reasons. First off, Mimi Wynant came across with the watch chain she plucked off Julia's body. It belonged to Clyde Wynant.

- What's the second reason?

- A pip!

- The bullet that killed Nunheim came from the same gun!

- That's all right, Inspector.

- All right? It's perfect!

- Clyde Wynant is guilty of both of those murders.

- Maybe.

- What?

- Fifty'll still get you a hundred.

[...]