Audemars Piguet Huitième Chronograph 18K Yellow Gold Ref. 25644

DETAILS
Manufacturer: Audemars Piguet
Model: Huitième Chronograph 
Reference Number: 25644.002 
Movement: Automatic
Condition: Very good
Gender: Men’s/unisex
Time Period: 1980 - 1986 
Retail / Compare-At Price: n/a collector's item
Our Best Price: $9,950

CALIBER
Movement: -
Caliber: 2126 (based on the Jaeger-LeCoultre caliber 889)
Jewels: 51

CASE
Case Material: 18K yellow gold
Case Diameter: 40 mm
Thickness: 11 mm
Waterproof: 70 ft. / 20 m.
Water Resistance: 2 ATM
Material Bezel: Fixed stepped 18K yellow gold with concave engraved blackened Audemars Piguet signature at 12 o'clock
Glass: Sapphire
Dial: Ivory
Dial Numerals: 18K rose yellow applied rectangular-shaped hour indices, black minute/chronograph fraction of a second scale, black Arabic numerals on the sub-dials, perimeter black tachymeter scale to 500 UPH around the outer rim

BRACELET / STRAP
Bracelet color: Black
Bracelet Material: Leather
Clasp: Fold-over
Clasp material: 18K yellow gold

FUNCTIONS
Chronograph, center-sweep chronograph seconds hand, yellow gold framed magnified square date aperture window at the 3 o'clock, three gold-ringed recessed ivory subsidiary dials including a running small constant seconds register at 12 o'clock, a 30-minute chronograph counter at 9 o'clock, and a 12-hour chronograph totalizer at 6 o'clock, hours, minutes, tachymeter scale, 45-hour power reserve

OTHERS
Round shape case
Blued leaf-shaped hours/minutes hands, black painted stick with wedge-shaped counterbalance chronograph hand, rose gold applied, black and red stick-shaped sub-dial hands
18K yellow gold chronograph pushers (start/stop - reset) at 2 and 4 o'clock
18K yellow gold solid case back secured with snap engraved with serial number
18K yellow gold push/pull knurled crown
The three-body case, downturned lugs, and bezel are brushed and polished.
This automatic self-winding Audemars Piquet caliber 2126 with a Dubois-Depraz module column wheel chronograph movement. It is rhodium-plated with fausses cotes embellishment. Constructed with an anti-shock system and a straight-line lever escapement. It includes a monometallic balance that's adjusted to heat, cold, isochronism and five positions, a self-compensating flat balance spring, a 21k gold rotor segment, and a hacking seconds mechanism for precision time setting.
This mechanism oscillate at a frequency of 28,800 vhp (4 Hz)
C serial
The Audemars Piguet Huitieme Chronograph 25644.002 was introduced in the 1980's.
Incomplete (with box, no papers)