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Why Do Pen Caps Have Holes? A Clever Design You Probably Overlook

Pen caps aren’t just to protect the tip—they feature tiny holes for some smart reasons:

1. Safety First:
The hole allows air to pass through if the cap is accidentally swallowed, reducing choking risks.

2. Better Ink Flow:
It helps balance the pressure inside the pen, preventing leaks and keeping your writing smooth.

3. Cost-Effective Manufacturing:
Less plastic is used thanks to the hole, speeding up production and saving money when making millions.

4. Stylish Touch:
Some brands turn the hole into a signature design element for easy recognition.

Next time you spot a pen cap, remember—it’s not a random hole but clever engineering in action!