Automatic movement with bidirectional winding 'butterfly' rotor. Used in Oyster Perpetual, Submariner 6536/6538, and Explorer models from the 1950s. Known for reliability and accuracy, with chronometer-grade variants.
Movement Type
Automatic
Jewel Count
25 jewels
Power Reserve
48h
Frequency
18,000 vph (5 Hz)
Diameter
28.5mm
Height
5.85mm
Rotor Type
central_rotor
Winding
automatic_bidirectional
Shock Protection
kif
