Daytona in-house chronograph, vertical clutch, 72h power reserve. Rolex's first fully in-house automatic chronograph (2000). Column-wheel chronograph with vertical/axial clutch, Parachrom Blue hairspring, ceramic ball bearing rotor (first use by Rolex), 3-6-9 subdial layout. Replaced by 4131 in 2023.
Movement Type
Automatic
Jewel Count
44 jewels
Power Reserve
72h
Frequency
28,800 vph (8 Hz)
Diameter
30.5mm
Height
6.5mm
Rotor Type
central_rotor
Winding
automatic_bidirectional
Shock Protection
kif
