TAG Heuer uses this movement for several years now (since 2009) and since the cancelation of the Calibre Ch80, it is the upper-grade engine of the brand. replica-watches The calibre 1887 is based on the Seiko 6S37 (or TC78) chronograph movement, which TAG Heuer acquired a license to manufacture with several major updates however. www.replicawatches.ink The differences between the Calibre 01 and the Calibre 1887 are first a redesigned rotor (coated in black), a column wheel coated in red (and not blued like in the 1887) and a different chronograph bridge. The rest of the mechanics is similar and so is the 6-9-12 layout.