In 1966, Hamilton acquired the Buren Watch Company of Büren an der Aare, Switzerland, including all factories and technologies that had been developed by Buren up to that point. From 1966 to 1969, Hamilton Lancaster and Buren Switzerland were operated as a joint concern, with Hamilton using a number of Swiss movements for their "American" watches and Buren utilizing a number of components manufactured by Hamilton Lancaster. It was during this time that Hamilton started to selectively incorporate the highly innovative Buren Micro-rotor (a.k.a.