Rolex Sea-Dweller (4000) vs Rolex Sea-Dweller (43mm Modern)

Side-by-side at a glance. Click a watch above to open the full reference page.

	Rolex 16600	Rolex 126600
Model	Sea-Dweller (4000)	Sea-Dweller (43mm Modern)
Caliber	Rolex Cal. 3135 -- in-house automatic, 28,800bph, 48h PR, 31j; Parachrom hairspring, Glucydur balance; long-running COSC-certified movement	Rolex Cal. 3235 -- in-house automatic, 28,800bph, 70h PR, 31j; Chronergy escapement, paramagnetic Parachrom hairspring, Superlative Chronometer
Case size	40mm	43mm
Lug-to-lug	47mm	48.5mm
Years produced	1989–2008	2017–present
Brand tier	luxury	luxury
Era	vintage	modern
Movement tier	In-house manufacture	In-house manufacture
Market median (excellent / full-set)	n/a	n/a
Typical range	n/a	n/a
Confidence	low	low
Categories	dive, sport	dive, sport
Editorial	yes	yes
Typical price (2026)	$4,500 – $7,000	$12,000 – $17,000
Service	Every 10 years · $900 – $1,400	Every 10 years · $900 – $1,500
Collector note	sleeper: The outgoing 40mm Sea-Dweller 4000 trades at a significant discount to the current 126600 despite sharing the same core DNA and a less polarizing case size.	most sought: The 43mm Sea-Dweller returned the "Sea-Dweller" red text to the dial for the first time since 1977, driving strong initial demand that has held through the current generation.