This is what is referred to as perforated material. It is a view-thru vinyl product that full-color graphics can be printed onto.
It is widely used for rear windows in vehicles because the nature of the material allows the driver to see out, but nobody can see in.
The perforated material is also used for businesses for their storefront windows, like this one that Centreville Sign A Rama produced for KiD to KiD here in Centreville.
