What’s the Hole in a Safety Pin For?

So let’s get a little nerdy for a second (don’t worry, I won’t get too deep). Making a safety pin involves machines shaping the metal wire into that exact shape. During this phase, the hole serves as an anchor point. Without it, it would have been difficult to consistently form that coil. Imagine it as a guiding pinhole. It keeps the wire steady as it’s twisted into that distinctive taut coil that provides the safety pin its snap and strength.

Many spring-based mechanisms use an equivalent feature during assembly to maintain tension and torque across each spring. So as small a detail as it may seem, that little hole is doing a lot of heavy lifting behind the scenes.

Thought It Was Only For Decoration
If you thought the hole was simply… there, you’re not alone. It doesn’t look functional. It’s little, discreet, and if you’re not a mechanical engineer or inclined to question everything, you probably never did. The design is minimalist to the point that it’s easy to not realize how much thought went into it.

Plus, it’s not as if the packaging has a tag saying, “Hey! This is for tension control!” The way most of us do is rip open a pack of safety pins and go to pinning.

Can You Use the Hole for Something Else?
Actually, yes. Though it was not intended for this purpose, some enterprising people use the hole to attach safety pins to other objects — by putting a ribbon through it or weaving a thin piece of wire around it and tacking the pin into something to prevent it from slipping. It’s not its intended use, but hey, it’s a little bonus feature if you’re feeling resourceful.