Introduced in the early 1980s, the Patek Philippe Nautilus ref. 3800/1 was the first mid-sized version of the original Nautilus 3700 from 1976. With a 37.5mm case diameter, it was designed to appeal to those who found the original "Jumbo" 3700 too large. Despite the smaller case, the 3800 retained all the key design elements of Gérald Genta’s original vision—the signature rounded octagonal bezel, horizontally embossed dial, and integrated bracelet.

This example features a sigma dial, indicated by the small "σ Swiss σ" markings at 6 o’clock. These symbols indicate that the hour markers and hands are made of gold. Another notable feature is the black date disc with white numerals, which was primarily used on the early production runs of the reference before Patek Philippe transitioned to a white date disc.

The movement in this reference is the Patek Philippe Caliber 335 SC, a significant evolution from the Jaeger-LeCoultre-based Caliber 28-255C used in the original 3700. Unlike its predecessor, the 335 SC features a central seconds hand ("SC" for "Seconde Centrale").