The reference 4300V/120R-B547 is the Overseas Perpetual Calendar Ultra-Thin in the form that most directly presents the watch's specific mechanical achievement: the skeleton dial through which the Calibre 1120 QPSQ — the "QPSQ" suffix identifying the Quantième Perpétuel Squelette, the skeletonized perpetual calendar variant of the 1120 base movement — is visible in direct view from the dial side rather than only through the exhibition caseback. The distinction between the skeleton variant (4300V/120R-B547) and the silver-dial variant (4300V/120R-B064) described in the adjacent entry is the distinction between two philosophies of how to present a perpetual calendar movement in a thin case: the silver dial presents the complication's displays (day, date, month, leap year, moon phase) as information on a refined surface, the movement beneath it suggested by the caseback view; the skeleton dial presents the complication's mechanism as the display itself, the movement's own components — the bridges, the gear train, the calendar wheels, the perpetual calendar's program wheel — the primary visual content of the watch's dial-side face. The skeleton version asks the viewer to read the time and the calendar from the same surface on which the mechanical means of producing both are simultaneously visible.
The Calibre 1120 QPSQ carries 36 jewels and a 40-hour power reserve. Its relationship to the 1120 QPSQ's base caliber lineage — the 1963-1967 three-manufacturer collaboration detailed in the adjacent 4300V/120R-B064 description — is unchanged: the 1120's founding as the VC deployment of the shared JLC/AP/VC base caliber, the QPSQ module's perpetual calendar architecture developed above it in VC's own manufacture, and the "SQ" suffix's skeletonization of both the base and the module for the transparent dial display. At 4.05 millimeters of movement thickness within the 8.1-millimeter total case height — the same thin profile as the silver-dial variant, the skeletonization removing material from both the base and the calendar module's bridges and plates rather than adding any thickness for the openworking process — the skeleton variant maintains the ultra-thin designation's dimensional achievement while adding the transparency that the dial-side architecture requires.
The skeletonized bridges and plates of the Calibre 1120 QPSQ — the material removed from each bridge and plate's non-structural zones to reveal the gear train and mechanism beneath while retaining the structural material whose integrity keeps the movement functional — are finished to the Hallmark of Geneva standard whose requirements apply across the full component surface rather than only to the visible faces. The Hallmark of Geneva certifies both the finishing standard and the production location in the Canton of Geneva. Each anglage on each skeletonized bridge edge is polished by hand; each non-structural cavity's inner surface is finished to the standard whose visibility through the skeleton's open architecture makes quality directly observable; each screw's head is polished with a chamfered slot whose finish is consistent with the movement's overall standard. The rose gold color that VC applies to the movement's components — the 18K 5N rose gold that matches the case material — means that looking through the skeleton dial is looking at a warm precious metal movement whose rose gold bridges and plates are visible against the sky-through-sapphire-crystal behind them, the warm gold of the skeletonized bridges providing the positive visual element against the neutral depth that the crystal's transparency creates.
The four perpetual calendar displays — day, date, month with leap year, and moon phase — are legible from the dial side through the skeleton's own architecture: the calendar's discs and sub-dials arranged within the openworked field in the positions that the Calibre 1120 QPSQ's movement architecture determines, each calendar indicator present and readable without a separate opaque sub-dial plate to carry it. The star-studded sky and two gold moons of the moon phase are visible at six o'clock, the moon phase's night sky and lunation display integrated into the skeleton's open dial field rather than enclosed in a separate moon phase aperture behind an opaque plate. The hour and minute indication uses the rose gold hands swept against the skeletonized movement field, the chapter ring at the dial's outer circumference providing the time reference against which the hands' positions are read.
The 18K 5N rose gold case at 41.5 millimeters in diameter and 8.1 millimeters in total height maintains the Overseas's established case architecture — the nautical porthole bezel reference, the brushed and polished surface alternation, the Maltese cross at the crown and bracelet clasp. The rose gold bracelet, plus grained calfskin leather and rubber straps in the three-strap interchangeable system, provide the wearing flexibility that the Overseas collection's quick-release mechanism enables across the 4300V/120R-B547's wearing contexts. Water resistance is 50 meters through the sealed case construction. The exhibition caseback reveals the Calibre 1120 QPSQ's reverse, the 22-karat gold wind-rose oscillating weight's rotation visible against the movement's own reverse face.
The 4300V/120R-B547 skeleton perpetual calendar's specific collector position is as the configuration that most directly places the Overseas Perpetual Calendar Ultra-Thin's dual achievement — perpetual calendar complication and ultra-thin dimension — in the viewing mode that makes both achievements simultaneously visible. The thin dimension is an engineering claim whose verification requires either trusting the specification or observing the case profile; the perpetual calendar is a mechanical achievement whose verification requires either trusting the complication description or observing the mechanism. In the skeleton variant, both can be observed directly from the dial side: the thin profile visible in cross-section, the perpetual calendar mechanism visible through the open dial face, the warm rose gold of the 1120 QPSQ's skeletonized bridges providing the specific visual quality that makes the observation as aesthetically rewarding as it is mechanically informative.
