Saw this in my IG ad.
Can this be applied on the outer layer of my windows? Inner side has window grille.

I general a tint will help only a little bit with the heat. I used Raybarrier before. If you have a real problem with heat and cant the glass to double glazing then you should place a shade outside in front of the window. That will reduce heat transfer into the house. Consider outdoor blinds. They are very efficient, though they loose to double glazing.

This tint will mostly help with UV reduction. For that purpose they are good.