What is it? 

A tempered glass screen protector is multi-layered with a bottom absorbent silicon, PET film, clear adhesive tempered glass, and oleophobic coating. Oleophobic meaning oil resistant. Tempered glass is up to 5 to 10 times tougher than normal glass for extra protection. 

Why use a glass screen protector? 

Honestly, do you really need one? We say yes. If you've spent hundreds of dollars on buying or upgrading to a brand new phone with an awesome display, would you really want to ruin it with scratches, dullness, or cracks? Every time you drop your phone, you risk cracking the screen. Sounds scary right? Because it's true.