This guy discovered the one thing that can damage the Apple Watch's nearly indestructible screen

If you plan on paying $US350 for the Apple Watch Sport, here’s some good news: it seems nearly impossible to scratch up its screen, as Lewis Hilsenteger of popular YouTube channel Unbox Therapy just discovered.

There is one material, however, that can do some real damage to the Apple Watch Sport’s display: sandpaper.

The Apple Watch Sport uses Ion-X glass for its screen, unlike the more expensive Apple Watch models that feature sapphire glass-coated screens. This means that the screens on the Apple Watch and Apple Watch Edition are much more scratch-resistant than that of the Apple Watch Sport, since sapphire is one of the hardest materials in the world — second only to diamond.

The Ion-X glass held up pretty well during Hilsentenger’s testing, until it faced two different types of sandpaper.

Here’s how the screen looked after it was scratched with standard sandpaper:

And here’s how it fared after it was scratched with a rougher type of sandpaper that uses aluminium oxide as the abrasive material:

But the display didn’t budge after it was repeatedly scratched with a knife:

Or a key:

Or steel wool:

Check out the full video from Unbox Therapy below.

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