Certainly, this is a Certina Blue Ribbon!? Yes, but is from a batch that was specially made to Volvo Cars to celebrate Volvo´s 50th anniversary in 1977.
This model was produced in quite some numbers, but we have not seen one as good. Therefore it has been given a full service, with both mainspring and crystal changed. Movement is caliber 25-651M with 26 jewels (The “25” stands for 25 mm movement diameter). Th stainless steel case is 36 and the thickness 12,3mm. Model reference is 913 1218 41.