51 Special

[RayCornett]

I recently acquired what is supposedly a 51 which I believe is a "Special" but have been told it is an MK1. Blue gray or,,,,,,,Navy Gray, stainless cap with black cone shaped jewel, steel(?) nib. However, I thought "Specials" said "Special" on the converter. This one only says " "Parker "51" ". Also, the number of times to squeeze the bar on the converter is 4. I heard that us one way to help date it as well.