Can aftermarket window film be installed over factory window tint?

As long as it is factory window tint, which is a color in the glass, then after market window film can be installed directly on the glass. Aftermarket window film has many more solar benefits than factory window tint. Aftermarket window film rejects 99% of ultraviolet rays and between 35%-60% of heat, depending on the film level used. Plus, adding aftermarket tint over factory tint can give you more privacy for storing personal items in the back of a vehicle.