TEMPERED GLASS Before buying my own personal tempered glass cover about a year ago, I had NO idea what this meant. After a little digging and researching, I found out it is made by heating the glass and then cooling it very quickly. This type of glass breaks differently than normal glass, creating more rounded edges of glass pieces instead of jagged shards that regular glass creates. A tempered glass protector is a multi-layered screen protector. It has a bottom layer of absorbent silicon, PET filmand an optically clear adhesive tempered glass and oleophobic coating in that order. Tempered glass is up to five times stronger than normal glass.