Avant Garde Extra Light  Suggested by pilaster 

Avant Garde Extra Light

Those "S"s are slightly different, IMO

Hmm...I do see your point...unless it's a version from a different foundry? Possibly the Ss have a slight modification?

It's worst if we speak about the P's...

Thank you everyone!

OK, "S" is definitely not AG. "C", "A", "O", "D" are identical. "P" and "E" with veeeery small differences.

Marking as suggested until we can resolve it, as its clearly either modified, more than one font, or possibly some variation that I've not come across before.