A fine and rare gold perpetual calendar chronograph wristwatch with register, tachometer and moon phases, Patek Philippe & Co., Genève, no. 868249, ref. 2499, First Series, 1951

18k, nickel lever movement, 23 jewels, bi-metallic compensation balance, precision regulator, 8 adjustments, silvered matte dial, applied arabic numerals, apertures for day and month below 12 o'clock, three subsidiary dials indicating constant seconds, 30 minute register and date combined with phases of the moon, outer ring calibrated for tachometer, circular case with flat back, concave bezels and stepped lugs, square chronograph pushers, case, dial and movement signed, accompanied by an Extract from the Patek Philippe Archives.

The accompanying extract records the date of manufacture as 1951 and its subsequent sale on April 17th of 1956.

The present watch, belonging to the first series, displays a rare design feature in its flat back and oversized lugs. For other examples of this construction, see two reference 2499's in Sotheby's New York, Important Watches Wristwatches and Clocks, October 27th, 1998, lot 434 and February 21, 2001, lot 292. Also for a reference 2497 with a similar flat back see Sotheby's New York, Important Watches, Wristwatches and Clocks, March 6, 2002, lot 285. 

The case of this first series watch is a remarkably well preserved example.  The gold marks remain clearly struck and the high definition of the lugs is nearly unheard of for a watch of this age. The overall condition of the watch suggests very little use over its lifetime.