The reference ST 105.012 is NOT the successor of the reference ST 105.003.
Speedmaster Reference ST 105.012 marks a particularly important stage in the Speedmaster story.
When production of the ST 105.002 model came to an end in 1964, its family line split into two branches:
– ST 105.003, heirs of the ST 105.002,
– ST 105.012 (the Professional branch) with a new shape of caseband designed to protect the pushers and crown from snagging.
It is interesting to note that reference ST 105.012 appeared in the first quarter of 1964, i.e. two to three months before the ST 105.003, a fact that had never been mentioned or even investigated before our research for the MOONWATCH ONLY book.
This model is thus the first of a line of Speedmaster Professionals, the descendants of which are still being manufactured in 2017.
What also makes the reference ST 105.012 interesting is its close historical link with the conquest of space.
NASA’s resistance tests to select a chronograph for its astronauts were carried out on the ST 105.003 (NASA reference 6049 according to the designation used in the USA), which was to be part of the official gear of the Gemini astronauts.
The ST 105.012, on the other hand (NASA reference 6126) was chosen for the Apollo missions without the need for new tests.
The model is also of interest because of the modifications of the dial, caseband and caseback during its production run.
4 sub-references have been produced between 1964 and 1968: 105.012-63, 105.012-64, 105.012-65 and 105.012-66. Production of all the versions is estimated at between 24,000 and 24,500 units. The least common sub-reference is 105.012-63, of which probably fewer than 2,000 were made.
During its first year of production, this reference was fitted with Professional dials without the T countermarks flanking SWISS MADE, and then with the countermarks (close or spaced Ts). There are also dials with the Ts asymmetrically printed on subsequently (see our article about Speedmaster dials here).
The ST 105.012 was a styling success with its short and wide pushers set well into the caseband.
The caseback of the ST 105.012 has a double bevel until case reference 105.012-65, and thereafter a single bevel.
It is also interesting to note that the casebands of some 105.012-66s have unusual lugs with a flat top and a ledge. This particularity, which has often been polished out, is associated with the firm, La Centrale Boites, which made some of the cases of the period about 2/3 of the 105.012-66s.
There has been much speculation over the origin for the Professional inscription on the dials of the reference ST 105.012 Speedmasters and the date it appeared.
Contrary to what was believed until recently, the Professional inscription was not added in July 1965, following NASA’s certification of the Speedmaster for its astronauts, as a kind of tribute to these super-professionals. If this is true, then all the dials of the models produced before that date shouldn’t have such inscription.
After lengthy research with the help of the OMEGA Museum, we can state that this version of the facts is not quite exact. The Professional inscription is a feature of the ST 105.012 model with the new caseband design and it appeared on the dial of this model from the start of its production during the first quarter of 1964.
The conclusive proof can be found on the first ST 105.012 models with case reference 105.012-63 and with movements numbered between 20.520.xxx and 20.521.xxx. Their dials have the Professional inscription but lack the Ts on either side of SWISS MADE. The T countermark was made mandatory by the Swiss government in 1964 to denote radioactivity in luminous dials. The production of dials with the T countermark started in April 1964, but the assembly and delivery of models with T-less dials could have continued until around July 1964.
The fact that Professional dials without Ts were fitted until the summer of 1964 proves that these were factory-fitted dials and confirms that the Professional inscription appeared well before July 1965 and has nothing to do with NASA’s certification of Speedmaster. Thus the 105.012-63 with its first two dial configurations could be seen as an historical representative of the first Speedmaster Professionals to be made.