Why Do Electrical Plugs Have Holes in the Prongs?

Why do phone charger plugs have those tiny holes in the prongs? They’re not decoration, and they’re not there by accident. This episode dives into the strange, century-old engineering story behind one of the most ignored details in your house: the holes in a standard North American plug. From Harvey Hubbell’s 1904 patent to modern safety lockouts, outlet retention, factory tooling, and the weird persistence of standards nobody can afford to change, this is the hidden history of a design you’ve used your entire life without noticing. If you like overlooked details, forgotten inventions, and the bizarre backstory behind everyday objects, subscribe to Weirdward Bound. 00:00 Intro 02:35 Dangerous Early Electricity In Homes 05:03 Harvey Hubbell Invents Plug Retention 07:17 Why Plug Prongs Got Flat Holes 09:22 The Debate Over What The Holes Do 13:08 Why The Holes Never Disappeared 16:35 Plug Standards Around The World 19:34 New Safety Uses For Plug Holes 22:27 Accidental Resilience In Engineering 25:06 Outro