The F Comp is named such because Smith and Wessons factory designation for the stainless K frame is 'F frame'.
(Standard catalog 3rd. bottom pg. 170)
I traded a model 27-2 blue 6" for this, and would do it again.
I do like the 3" model 66s', maybe too much.
I'm working on a complete set ,and searching for the elusive 'Super K" .
As best as i can figure ,the PCP serial prefix stands for
'Performance Center ,Ported' mine is #157 of 300 supposedly made.
Here are the pictures.
Good luck to you in finding your grail gun,this certainly is one of mine.
Wearing a set of grips handcrafted by VM.
Here ,with the rest of the bunch.
66-2 1985 ,66-3 1988 ,66-3 F comp 1993 ,66-4 magna port 1996 66-5 3.25" 2001 , 66-5 3.25" 2002.