A viral video has stunned internet users after it revealed the reason why ballpoint pens have a small hole in the lid.
Zack D, who often shares videos on his Instagram of his fascinating discoveries, told followers most people thought it had something to do with the ink when in actual fact that was not the reason at all.
"It is much more important than that," he said on the video.
"Pen companies are actually required to add these little holes.
"You see, there's just enough space for airflow if the cap gets stuck in someone's throat."
Many of his followers were shocked by the discovery.
"I remember chewing this pen cap during my childhood," one commented.
"Most people, including me, like to bite the pen cap," somebody else added.
"Wow hopefully [swallowing the lid] never happens to anyone," a third said.
Many others however were baffled it wasn't already common knowledge.
"Everyone knows this by now," one said.
"I thought this was common knowledge," a follower questioned.
"Yes wtf, I knew it when I was 6-7 [years old] even though I never chew on my pens," somebody else claimed.
Pen company Bic has confirmed the reason for the hole in the lid on the FAQs section on its website.
"The reason that some BIC® pens have a hole in their cap is to prevent the cap from completely obstructing the airway if accidentally inhaled," the website states.
"This is requested by the international safety standards ISO11540, except for in cases where the cap is considered too large to be a choking hazard."
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