RE: [Demo notebook] Reference notebook: corrections and recurring beginner questions · RWI-10720

Case 11 — Beginner glossary Q&A: complication, caliber, jewel count, power reserve

Caliber is the movement's model designation, like a part number. Two watches from different brands can share the same caliber family with different finishing or regulation. On a spec sheet it tells you what's inside and roughly what service parts are available. It doesn't tell you how well that particular example was adjusted.