The PHILLIPS Hong Kong Watch Auction: XXI takes place on 21-23 November 2025, at our West Kowloon headquarters. The auction includes more than 300 of the world's finest watches – and though we are loath to boast, we truly think it's one of the best catalogues we've ever put together. We'll be highlighting a number of the most interesting lots and stories featured in the sale right here, including the unusual transitional Rolex Daytona seen below.
– By Logan Baker
Produced from 1951 to 1985, the Patek Philippe Perpetual Calendar Chronograph Ref. 2499 represents not just a pinnacle of postwar Swiss watchmaking, but the clearest thread connecting vintage Patek Philippe to the modern era.
Across four distinct series, subtle evolutions in the ref. 2499's case, dial, and crystal chart the progression of both technology and taste over three decades.
By the time the fourth series of the reference debuted in 1978, the 2499 had reached its most mature form: round chronograph pushers, applied baton hour markers, an outer seconds track, and – most notably – a sapphire crystal, replacing the domed acrylic of earlier generations.
Yet even within this “final” version, there’s a fascinating variation known only to those who look closer: the MK 1 case, produced by the long-time Geneva casemaker Wenger before Patek Philippe brought case production in-house via Ateliers Réunis in 1982.
Of the roughly 120 examples of the fourth-series 2499 produced, only about 46 were made in the Wenger MK 1 case. They represent the very last 2499s Patek Philippe ever fitted with cases made by an outside supplier – a notable milestone in the brand’s move toward vertical integration.
The Wenger MK 1 case is a study in refinement and restraint. Measuring 37.5mm in diameter, it’s slightly larger than earlier Vichet-made cases and features a domed back, short lugs, and a three-piece construction with a snap-on bezel and caseback.
The MK 1’s proportions are subtly different from the later Ateliers Réunis MK 2 cases: the crown is marginally larger, the pushers sit a touch higher, and the bezel profile appears more dynamic.
Wenger, marked by a tiny key with the number 1 inside, had been crafting cases for Patek Philippe since the 1930s. When the firm began working on the 2499, it followed Emile Vichet, who had made the earliest examples with sharply downturned, almost claw-like lugs and a flat caseback.
Wenger’s interpretation softened those lines, creating a more balanced and ergonomic shape. By the 1970s, as case design evolved alongside new manufacturing techniques and a shift toward daily-wear usability, Wenger’s fourth-series cases embodied the sophistication that defined the end of the mid-century era.
The fourth-series, 18k yellow gold 2499 from 1980 that's offered at the upcoming Phillips Hong Kong Watch Auction: XXI belongs to this rare MK 1 subset – and ranks among the finest surviving examples. Its solid yellow-gold dial, crafted by Stern Frères, shows no signs of restoration, retaining its original silky finish. Every printed inscription is sharp and fully legible, the calendar windows are perfectly cut (by hand!), and the gold Dauphine hands match the untouched subsidiary registers. The gold moon-phase disc, with its deep blue champlevé enamel night sky, adds a flash of color to an otherwise austere composition.
The case hallmarks are crisp, the circular satin finish on the caseback is intact, and the lugs are thick, with pronounced and crisp fluting. Even the engraved numbers – “160” inside the bezel, and “399” beneath the dial – remain perfectly visible.
There’s also a touch of market lore: this very watch last appeared publicly at the May 2019 Phillips & Blackbird: SPORTS auction in Hong Kong, where it achieved HKD 5,070,000. Since then, it has remained in a major European collection, untouched and preserved in the same condition.
When Patek Philippe acquired Ateliers Réunis and began producing its own cases, it marked the end of an era. The Wenger MK 1 thus stands at a crossroads: part of the great outsourced tradition that defined Geneva’s golden age, yet also a precursor to the brand’s modern independence.
You can view the complete Phillips Hong Kong Watch Auction: XXI auction catalogue here.