3 Things to Know About Using Grounded vs. Ungrounded Extension Cords

Use a grounded three-prong cord for anything with a metal case or a three-prong plug The third prong connects to your breaker panel’s ground wire. If something fails inside a device like a power tool or refrigerator, that prong gives electricity a safe path to trip the breaker instead of traveling through you.

Use an ungrounded two-prong cord only for double-insulated devices with two-prong plugs Phone chargers, lamps, and small electronics are designed not to need a ground. Buying a two-prong cord for a three-prong device removes a safety feature, not saves money.

The only good reason to buy a two-prong cord is for an older two-slot outlet Even then, a five-dollar adapter with a ground tab often works fine. Otherwise, always get the grounded cord — it is cheap insurance.