The Scuba Museum has been very fortunate to locate a low serial number black label Kajman regulator.  Only the first Kajmans were made with the black label and only used in military applications officially.  The Kajman became a favorite of military divers and many Kajmans found their way to civilian hands through unconventional means.  The regulator itself does not appear to be any different except for the label, but are a bit harder to find in the USA.  This model is in very nice shape and quite dive worthy.

Black Label Kajman in action gallery.