Equipped with a white dial and the caliber 631 'MecaQuartz' chronograph movement, the IWC Portofino Chronograph IW3731-02 has a 35.00mm yellow gold case. This model was sold from roughly 1988 to 1998.
Movement Type
Quartz
Caliber
631Jewels
25
Hands
Small Seconds
Shape
Round
Lug Distance
18.00 mm
Material
Yellow Gold
Glass
Sapphire
Thickness
7.80 mm
Diameter
35.00 mm
Water Resistance
30.00 m
Dial Color
White
Material
Alligator