We take a lot of objects and items that we use every day for granted.

But did you know some of them have incredible hidden components that are actually designed to save your life?

From secret details in planes and cars to little known features on your phone, backpack, and even pen lid.

So get ready to find out the true life-saving purposes of the things hidden all around you.

You're listening. You're listening. You're listening. the true life-saving purposes of the things hidden all around you.

You're listening. You're listening. You're listening. You're listening. You'd be amazed.

When you look at an aircraft engine, you can't really tell if it's running or not.

While it might be tempting to take a closer look to confirm, you should stay back. Because, even from 16-ft away, some jumbo jet engines are powerful

enough to suck incredibly heavy items straight into them. So how can the ground crew tell

if they're in danger of being sucked in and sliced to ribbons? Well, I'm sure you have already noticed the spirals painted

on the central cones of the engine. When the engine's off, it looks like an unassuming decorative detail.

But when they're running, the spirals become obvious white blurs, depending on the rotation speed.

So it's pretty easy to see when it's a super spinning thread or not. Although it's not just ground crew, these spirals are designed to save.

Major aircraft manufacturers argue that this design keeps birds from flying into the engines when they are airborne, with the high-speed spirals apparently scaring them away.

Although you'd assume the ear-splitting noise of the aircraft alone

would be enough to keep them from thinking it was a safe place to rest. But I guess evolution works

in mysterious ways. If you're interested in delving more into the spirals and jet engines, I dedicated

a full episode to it. Check it out. Now, if you've ever sat in the window seat of a plane,

you've probably noticed the tiny hole at the bottom of your quasi-rectangular window.

While a lot of people don't think much of it, it's actually essential for keeping you safe

when you're up in the air. It all comes down to cabin pressure because the higher the plane

climbs, the less oxygen there is. At a

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