Omega Speedmaster*** 105.012-66 CB*** 1966
OMEGA Vintage Speedmaster Professional CB CASE Ref. 105.012-66, Calibre 321
Serial # 2495XXXX
Circa: 1966

DESCRIPTION: Omega vintage ‘Pre-Moon’ Speedmaster Chronograph, nicely aged patina, great condition. Very rare La Centrale Boîtes of Bien (CB) made case with unique ‘flat’ lyre lugs, circa 1966

MOVEMENT: Caliber 321, hand-wound mechanical column-wheel chronograph, 17 jewels

DIAL: Original iconic black dial with three registers, luminous baton markers with nicely aged patina, T SWISS MADE T

CASE: 41.7mm, Stainless Steel, originally aged case in fair condition, plexiglass

BRACELET: Omega Stainless steel stretch link bracelet, Ref 1506, endlnks 516, date stamp on buckle 3.66


According to the Omega Museum, this watch was sold in Switzerland in September 1967.

Firstly, nearly all Cal. 321 Speedmaster cases that you see were made by Omega case-maker, Huguenin Freres & Co, le Locle, Switzerland and consequently signed "HF" in the case-back. Only in 1966 with the reference 105.012 did Omega use an additional case-maker, and signed "CB" in the case-back.
What is unique about these CB made lyre lug cases is that the top of the lugs are flat and an angle can be seen from the top.
Hodinkee article about 105.012-66 with the case made by La Centrale Boîtes of Bien:

The highly collectible Omega chronograph Calibre 321 was first introduced in 1942 and was a collaborative project between Omega and Lemania, one of Omega's subsidiaries at the time, who supplied it as an ebauche (Lemania cal. 2310). The Calibre 321 is recognised as one of the best example of lateral clutch, column wheel controlled chronograph and Breguet, Patek Philippe and Vacheron Constantin sourced it as a base movement for a variety of chronographs. In 1946, the movement was further improved by developing its anti-magnetic shield and shock absorption, which would both allow it to become the champion during the NASA testing for the Apollo 11 mission.
Curiously, Omega only learned about the Speedmaster’s journey into space after seeing a photograph of Ed White taken during America’s first spacewalk as part of the Gemini 4 mission in June of 1965. The watch was attached to the arm via a long nylon strap secured with Velcro.
Following the discovery, Omega decided to add the word "Professional" to the product name, thus becoming Omega Speedmaster Professional. The new reference number was 105 or 145.012.