So what the heck is 3M masking film anyways? Rolls of masking film combine painter’s tape, sheet plastic, and static electricity, giving the ultimate cover-up for large windows, especially when using a paint sprayer. Painter’s tape allows you to mask precisely up to the edge of a window, while the pre-attached plastic film unfolds to cover the window. Static electricity helps the film stick to the window. You can find this stuff on my website www.theidahopainter.com