Books wanted for our men in camp and over there; take your gifts to the public library" poster
The pattern
This still is filed under Demonstration ad.
Define
The product does the arguing. The viewer sees the thing work, not a slogan about the thing working.
Mechanism
Proof by performance. The claim is the action: a visible, testable result the reader can replay.
Verdict
We can show a result in seconds
Why it works
The visual exaggeration of the massive stack of books makes the need obvious and memorable. It juxtaposes the tough, combat-ready soldier with a voracious appetite for reading, humanizing the troops while delivering a crystal-clear call to action.
Steal this when
You have a very simple, physical donation request and want to make the need visually unmistakable.