The rotating bezel to perform general calculations and navigational computations.
Reference
8557CALTVD-a1
Case Diameter
47.5 mm
Dial color
black
Movement (Type)
automatic
Movement (Caliber)
Valjoux 7750
Case Material
stainless steel
Case Surface
matt
Water Resistance
3 ATM
Glass
mineral crystal
Case Back
glass back
Band
leather strap
Origin
Swiss Made