Answer
Car One-Way Vision is only material recommend for vehicles. That is because Car One-Way Vision Film is specially-designed to maintain driver visibility on all vehicle windows thanks to its unique perforated construction. It is applied to the outside of the window.
Car One-Way Vision Film is made of polyvinyl chloride (PVC), with up to 50% of the film micro-perforated to achieve the desired image resolution and one-way visibility. For car rear window graphics, One-Way Vision Film is a 50/50 perforation pattern with 1.5mm holes, 8 mil, 2-year film.
The one-way visibility protects your privacy and driving safety. Due to the nature of perforation pattern, there is a slight difference in visibility depending on the angle of the window. The more vertical the window angle, the better visibility. Graphics printed on perforated window films tend to look less-vibrant than those printed on solid vinyl, because up to 50% of the window vinyl is missing (due to the perforation process).