Sorry if I mislead you, Cindy. I typed the "eff" to emphasize it. My mistake. It's f17, like f seventeen. I know it's getting late now, 'cause I'm screwing up my own meanings.
Okay, I have ASDFGHJKL: printed backwards on my forehead. I'm going to bed.
No problem.
Well, it could be an office number
or maybe a jet.
Here's a photo and a description of an
F-17 Cobra.
http://www.globalsecurity.org/military/systems/aircraft/f-17.htm