The IWC Portofino Chronograph IW3731-03 incorporates a 35.00mm stainless steel and yellow gold case, a white dial, and the caliber 631 'MecaQuartz' chronograph movement. It was offered from about 1988 through 1998.
Movement Type
Quartz
Caliber
631Jewels
25
Hands
Small Seconds
Shape
Round
Lug Distance
18.00 mm
Glass
Sapphire
Thickness
7.80 mm
Diameter
35.00 mm
Water Resistance
30.00 m
Dial Color
White
Material
White
Buckle
Alligator
