It's officially called a "Movement Form D," comes padded for convenience, and has something like 13 or so fill-in-the-blank lines covering a myriad of situations so that the train crew can easily fill in those blanks and read it back as a complete document. This may have been mentioned, but it is still used by the NS crews in, I believe, its original form save for the railroad initials.
The FALLSTON FLAGSTOP Railfan B&B
62 Beaver Street
Fallston, PA 15066