It’s something most people have seen—but rarely noticed.
Just beneath the faucet, near the upper edge of many sinks, there’s a small opening. It blends into the porcelain or stainless steel surface so seamlessly that it often disappears into the background of daily routines.
You wash your hands, brush your teeth, rinse dishes—never thinking twice about that quiet detail.
But that small opening has an important job.
It’s called the overflow drain, and it acts as a built-in safeguard against one of the most common household accidents: water
