Perforated window film, or window perf, is a semi-transparent vinyl film with a pattern of tiny holes that allows for one-way visibility, displaying a graphic on the outside while enabling occupants inside to see through to the other side. It’s used for advertising on vehicles and storefronts, providing privacy, and reducing glare and heat. The film’s perforated ratio, such as 70/30 (X% print, X% holes), determines the visibility and graphic clarity, allowing for custom choices based on project needs.