ROLEX REF. 6239 COSMOGRAPH
DAYTONA UNDERLINE DIAL STEEL
Rolex Cosmograph, Daytona, case No.923332,
Ref. 6239/6238. Made circa 1963.
Very fine and unusual, water-resistant, stainless steel
wristwatch with round button chronograph, registers,
tachometer, steel bezel graduated to 300 UPH.
Three-body, polished and brushed, screw-down case
back and crown, tachometer on the bezel graduated to
300 units per hour, inner case stamped with Ref. 6238.
Bi-color black and silver with applied faceted steel
baton indexes and luminous dots, outer 1/5th seconds
track, subsidiary silver guilloche dials for the seconds,
the 12-hour and 30-minute registers, silver pint underline
beneath Cosmograph. Luminous steel baton hands.
Cal. 72B, rhodium-plated, 17 jewels, straight-line lever
escapement, monometallic balance, shock absorber,
self-compensating free-sprung Breguet balance spring,
Microstella regulating screws.