This Duro Dakovic HR-M74 circa 1970's came to The Scuba Museum brand new.  It appears to be a clone of the Spirotechnique Royal Mistral.  The nozzle is oversized for US tank valves and the yoke is very short limiting its practical use in the US without modification.  This model when opened was heavily greased and had to be cleaned before using it.  It is unclear if this was simply a protective coating or simply a ill-advised set up method.  There was also a civilian version of this regulator produced called the Jadran.  It appeared to be the same regulator with a nicer blue themed label.  One unique feature to this regulator is that the inhalation and exhaust horns are switched from the to common inhalation on the right and exhaust on the left.  It is unclear why the Croatian/ Yugoslavians made this seemingly insignifigant change.