LONGINES | Ultra-Chron Automatic 70s Yellow Gold Square Case. Vintage Ref. 7924
Ref: 7924
LONGINES | Ultra-Chron Automatic 70s Yellow Gold Square Case. Vintage Ref. 7924
ULTRA-CHRON self-winding mechanical movement Caliber L431 with hours, minutes, center seconds and date. 36,000 vibrations per hour, 25 jewels, 42-hour power reserve, non-magnetic. The high frequency number required, in the late 1960s, the design of a new type of escapement wheel equipped with 21 teeth instead of the traditional 15 and a dry lubrication system with molybdenum disulfide.
Square case in yellow gold with polished finish measuring 30 x 30 mm.
Silver dial with applied indexes. Ultra-Chron logo at 6 o'clock and winged hourglass at 12 o'clock.
Date window with opening between 4 and 5 o'clock
Esalite crystal. Signed crown.
Yellow gold case back with pressure closure.
Original Longines black leather strap with original yellow gold pin buckle with winged hourglass.
YEAR: 1970s
CONDITIONS: EXCELLENT
ORIGINAL BOX: Absent
ORIGINAL WARRANTY: Absent
REVIEW: Performed in our laboratory