For most of its 50 years, the Monaco, whether Heuer or TAG Heuer, has had a movement that was produced by a supplier, which is not the outrage that newcomers to horology often think. As has been pointed out very often, here and elsewhere, the traditional practice in watchmaking has been to rely on movement suppliers and you didn't generally boast about the movement (there were exceptions but I'm speaking here of the general case) because you were using the same movements as your competitors. (There are caveats to this but again, it's general case we're talking about here, not the exceptions.) There is a sense in which the original Monaco used an in-house movement, or at least an in-house-ish movement, in the Caliber 11, which was produced by a consortium of makers of which Heuer was a member; but as a rule, supplied movements have powered the Monaco. There are of course things like the Monaco V4 of 2009, which had a belt-drive system intended to evoke an auto engine, but up until now, supplied movements have been instrumental in keeping the Monaco both reliable and affordable.