Reference:4925: Difference between revisions

== Movement notes ==

The 4925 runs the Aegler Cal. 10½ ligne Hunter family — the same caliber lineage that powers the contemporary Bubbleback line and the 4365 / 4444 / 4499 sister Air-references. The "Hunter" designation refers to the 700-series base architecture: caliber 700 / 710 / 720 / similar, with running updates across the production window. Manual wind, central seconds, 15 jewels in the early production, 17 jewels as a running update later (Sotheby's lot 190 catalogues "17 jewels, stamped ROW"). 18,000 vph, non-chronometer, no shock protection in the earliest examples.

=== Silvered ground with applied Arabic numerals (late production) ===

Sotheby's lot 190 (2020) catalogues a 4925 with a silvered dial and alpha hands, the case dated by serial number 354,085 to c.1956. The lot's catalogue text records only "Dial: silvered" and does not describe the marker style; the lot's own photography shows the same applied Arabic-numeral layout as the canonical eggshell dial, not baton indices. The example reads as a late-production 4925 made out of bridging stock as the 6552 was taking over, carrying the applied-Arabic dial forward onto a silvered rather than eggshell base.

== Case and construction ==

34mm stainless steel three-piece Oyster — case middle, threaded caseback, threaded crown. The case profile reads closer to the post-war flat Oyster than to the pre-war Bubbleback proper; the Cal. 10½ Hunter doesn't need the rotor-clearance dome. Lugs are 19mm with drilled spring-bar holes. The bezel is fixed and steel and smooth. The crown is a manual-wind brevet, screw-down, no Twinlock; the 4925 predates Twinlock, which arrives in the 1950s on the Oyster sport line.

The case is steel-only across documented examples. The 4444 (Air-Lion / Air-Giant / Air-King) carries a documented two-tone construction with a solid-gold bezel and crown, but the 4925 is consistently catalogued in plain steel. Sotheby's lot 190 (2020) gives 33mm rather than 34mm — within measurement-method tolerance for a watch usually quoted at 34mm. Across all surfaced major-house lots the case dimensions read consistent.

The caseback exterior is smooth without a date stamp. The interior carries reference and case-number markings. Roman-quarter date codes (II.46, III.48, IV.51, etc.) inside the caseback are the cleanest per-watch dating tell. Drilled spring-bar holes are period-correct on the 4925 lugs and persist into the 5500 era; the convention on the 4925 is consistent with the broader pre-1990 vintage Rolex line.

== Bracelets, end-links, and clasps ==

The 4925 era pre-dates the formal numbered Oyster bracelet references that anchor the later Air-King line. Period-correct fitment is a 19mm rivet Oyster with the early 6635-class end-links. The 7205 rivet Oyster (with end-link 57) that becomes standard on the 5500 also turns up on late-production 4925s and on service-era refits — Baer & Bosch lot AN3907 documents a 4925 case fitted with a 7205 dating from 1967 (clasp date code), making it a service-era refit rather than original delivery. Bracelet originality on a 4925 needs case-and-clasp-date verification rather than relying on the bracelet reference number alone, and most surviving 4925s wear bracelets that post-date the 4925's own production by a decade or more.