If you need an all-weather safety whistle for your emergency kit, the Storm Whistle ain't the prettiest thing you'll find but it sure gets the job done. It bills itself as the loudest whistle in the world at ~120db, and while I don't have a decibel meter to test that for myself, it is pretty darn loud — enough to be heard over crowds, machinery, and explosions, through glass, and most famously, underwater up to 50 feet.

Whenever and wherever you need to signal for help in an emergency situation, this is the whistle you want to have. Get it for just $6 on Amazon. For a smaller version that's easier for kids to hold, check out their only-slightly-less-powerful Windstorm whistle.