Something people from the south shore of Nova Scotia say when they're referring to something that is tough, they could just use the actual term Tough as Nails
but, they don't.
Guy1:HURHURHUR I'M SOO TOUGH HE HE!
Guy2:NO!!! YOU'RE HARD AS NAILS!!! HURHUR
NotStupidGuy: Um, the actual term is tough as nails, guys.
Guy1:NOOOO! YOU'RE WRONG!!