The Blancpain Fifty Fathoms Act I is powered by the manufacturer's caliber 1315, which has been serving reliably since 2007. The movement uses a silicon balance spring and offers a
link five-day power reserve thanks to its three-barrel
link construction. For this anniversary model, Blancpain added one special touch: a commemorative engraved platinum rotor, visible through the sapphire caseback (70
link years is the "platinum jubilee," get it?).
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