At first glance, that tiny hole in your pen cap might seem like a random design flaw—or maybe just a manufacturing shortcut. But it’s actually a brilliant safety feature that could save lives.

The hole in the cap of a pen is there to prevent choking. Many people, especially kids or those deep in thought, tend to chew on pen caps. If someone accidentally swallows it and it becomes lodged in their throat, that small hole allows air to pass through—buying precious seconds until help arrives.

This design was introduced by companies like BIC, which made it a standard in their pens starting in the 1990s after several tragic choking incidents. Today, most major pen manufacturers have adopted this simple yet life-saving feature.

So next time you see that little hole, remember: it’s not just a quirk. It’s a quiet guardian, hidden in plain sight.