LONGINES DIVING CHRONOGRAPH STEEL
Longines, Ref. 7981-1. Made circa 1966.
Fine and rare, water-resistant, large, tonneau-shaped,
stainless steel wristwatch with round button chronograph,
Three-body, polished and brushed, revolving bezel for
the elapsed time calculation, screw-down case back.
Bi color, black and silver with painted tritium baton indexes,
outer seconds/minutes division, outermost tachometer
scale, subsidiary dials for the seconds and 30-minute
registers. Luminous steel baton hands.
Cal. 30CH, rhodium plated, 18 jewels, straight line lever
escapement, monometallic balance, shock absorber, self
compensating Breguet balance spring, index regulator.