Locking connectors keep cords plugged in when they'd otherwise yank loose.

That’s it. Most extension cords rely on friction (the blades gripping the outlet). A locking connector adds a twist-and-latch mechanism that prevents accidental disconnection.

You’d need one if the cord will be pulled, bumped, or vibrated. Think job sites (saws, compressors), outdoor events (string lights, power tools), or RVs. Basically anywhere the cord might get snagged and yanked out of the outlet, leaving you in the dark or with a tripped breaker.

For indoor use where the cord just sits there? You don’t need a locking connector. A standard one is cheaper and easier. But if you’re moving gear around or working in a garage, the extra cost is worth avoiding frustration.