Have you ever noticed the two small round holes near the tips of many electrical plug prongs and wondered why they exist? While they may seem like a minor or decorative detail, these holes are actually the result of practical engineering. Found on many standard plugs, especially in North America, they serve several important functions related to safety, stability, and manufacturing efficiency

One key purpose of the holes is to help create a more secure connection between the plug and the wall outlet. Inside many outlets are spring-loaded contacts designed to grip the prongs firmly. The holes allow these contacts to align more precisely, helping the plug stay in place once inserted. A snug fit reduces the chance of loosening over time, which can lead to poor electrical contact, flickering power, or excess heat.

This design also contributes to everyday safety in subtle ways. When a plug fits securely, it is less likely to be partially pulled out, reducing exposure of the metal prongs. That lowers the risk of accidental contact, especially in busy households. While the holes are not a substitute for proper safety precautions, they support the overall reliability of modern electrical systems.

Beyond home use, the holes are helpful during manufacturing and packaging. They allow plugs to be held in place during production, testing, or shipping, and make it easier to attach tags or seals. This small feature helps reduce waste, improves efficiency, and keeps products organized—showing how thoughtful design often hides in plain sight.