The science behind our 3D-edge tempered glass

Every Kara tempered glass starts as a 0.33 mm float-glass blank. We chemically temper each one via ion-exchange — sodium atoms in the surface layer get swapped for larger potassium atoms, creating a compressive stress that gives the finished sheet its 9H scratch resistance.

After tempering, the glass is precision-cut to the exact dimensions of the target device, then coated with a fluorine-based oleophobic layer that survives 12 months of daily-use wear without losing its hydrophobic touch.

The 3D edge is what distinguishes a Kara protector from a flat-edge competitor: rather than sitting on top of the screen with a visible bezel, our edge wraps the 2.5D curvature of the device, eliminating the air gap that traps dust and ruins clarity over time.