spyder9, they never say anywhere that this actually is a CK 1 capsule; they repeatedly evade by saying "sound from the CK 1" etc. I wonder if it's even an externally polarized condenser like the original, or whether it's an electret as in their "reissue" C 451 B.
They also say that the original was from the 1980s, but I was using C 451s in 1973, and they weren't exactly new then.
--In AKG microphones of this period if I recall correctly, an "E" suffix indicated an XLR output connector; alternatives included "C" for Tuchel and "L" for Lemo. A pad switch was often present on models with "B" in the name, if there was such an available version, but the "B" clearly referred to the low-cut switch.
--best regards