A padlock may seem simple, but it’s one of the most dependable tools for protecting belongings — from bikes and sheds to toolboxes and gates. Built to handle weather and force, these locks also include a tiny feature most people overlook: the small hole at the bottom.
That little hole serves a crucial function. Since padlocks are metal, they’re vulnerable to rust and moisture buildup. Rain, humidity, and temperature changes can cause water to collect inside, damaging the inner mechanism.
The bottom hole acts as a drainage point, allowing trapped water to escape. This helps prevent corrosion and keeps the lock working longer.
Although the drainage hole was once a major innovation, many modern padlocks are now weatherproof and built to withstand year-round exposure. Still, classic padlocks with the hole remain popular because they’re strong, affordable, and easy to maintain.