"F1" through "F7" are just internal labels assigned by a PDF generator (like a virtual printer).
It was a typical day at the design studio, with the usual chatter and hum of computers in the background. But little did anyone know, a mystery was about to unfold. The team was working on a project that required a very specific font - CID font, to be exact. The client had requested a unique font, and the team was determined to deliver. CID font F1 F2 F3 F4 F5 F6 F7 Fonts Free Download