ROLEX, REF. 6240 COSMOGRAPH
DAYTONA STEEL
Rolex, case No. 1298338, Ref. 6240.
Made circa 1965.
Very fine and extremely rare, early, water-resistant,
stainless steel wristwatch with round button
chronograph, registers, tachometer, anti-reflective
black bezel and a stainless steel riveted Rolex
Oyster bracelet.
Three-body, polished and brushed,
screwed-down case back (Ref. 6239), buttons
and crown, tachometer graduation on the
bezel to 200 units per hour.
Bi-color silver and black with applied steel
baton indexes and luminous dots, outer 1/5th
seconds track, subsidiary dials for the seconds,
the 12-hour and 30-minute registers. Luminous
steel baton hands.
Cal. 722, rhodium plated, 17 jewels,
straight-line lever escapement, monometallic
balance, shock absorber, self-compensating
free-sprung flat balance spring, Microstella
regulating screws.