What is this close-up picture? (WotsThat: Hole punch)

Question

What object is shown in this zoomed-in close-up photo?

Neo1eon · Accepted Answer

Hole punch. The hole punch was invented in 1886 by Friedrich Soennecken, a German businessman, to help organize his filing system. His design became so popular that it's remained virtually unchanged for over a century, making it one of the most durable office innovations ever created.

Answer: Hole punch

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