its a clamp, bracket or spacer from an earlier period of time where Heuer's production was in-house.
Its much to sturdy built to be a direct tool on a wactch. The Heuer symbol is not inversed so i dont beleive its intended to stamp the emblem on anything such as would be the case with a brake press. But it could well be a spacer to hold a mould or form in a dye.
As i'm writing i just thought could it be used as a brace to hold a model steady for a lapping machine - hmmm.
- Darren

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