UNIMATIC Modello Uno Pro Diver 600m

Unimatic’s expansion of the ProDiver series introduces the Modello Uno references U1S-PD6-B and U1S-PD6-RB, shifting the brand’s output from standard recreational dive watches to professional-grade instruments calibrated for 600-meter depth ratings. The transition from a baseline 200-meter resistance to a 60-atmosphere threshold requires substantial re-engineering of the external case architecture, specifically regarding structural rigidity and gasket integration. While the brand initially gained traction by stripping away traditional dive watch elements to achieve a minimalist dial, these new references reintroduce specific functional indices and minute tracks necessitated by occupational diving requirements. The Modello Uno platform has been modified to accommodate thicker sapphire crystals and reinforced case backs without drastically altering the external silhouette that defines the manufacturer's catalog. Producing a 600-meter diver inherently demands tighter manufacturing tolerances, particularly at the friction points between the screw-down crown and the case tube, to prevent helium or water ingress under severe pressure.

The historical context of the 600-meter dive watch places it squarely in the domain of commercial saturation diving, where equipment is subjected to prolonged exposure in hyperbaric environments. Achieving this rating on the U1S-PD6 references involves individual pressure testing for every unit rather than batch sampling, ensuring that each case meets the specific 60 ATM operational standard. This standard dictates that the watch must withstand pressures equivalent to 600 meters of static water column, a metric that far exceeds recreational scuba diving limits but provides a massive safety margin for dynamic pressure spikes. By focusing on material endurance and legibility over decorative finishing, Unimatic positions these models as pure utility items. The references are split strictly by dial color and attachment options, offering a matte black iteration alongside a high-contrast reflex blue variant, both utilizing the same internal mechanics and case dimensions to maintain production consistency across the limited run.

The Case and Dial

The case architecture utilizes 316L stainless steel, an austenitic alloy chosen for its high resistance to pitting corrosion in chloride-heavy marine environments. The dimensions measure 40mm across the main case body, expanding to 41.5mm at the outer edge of the bezel assembly, providing a distinct overhang that facilitates bezel manipulation when wearing thick neoprene dive gloves. The surface finish is entirely brushed, displaying a distinct linear graining along the lug tops and case flanks that eliminates light reflection and hides surface abrasions acquired during hard use. Unimatic has retained the drilled lugs with a 22mm width, a mechanical specification that allows for the rapid deployment of a straight spring bar tool to push the pins out from the exterior, significantly reducing the risk of scratching the inner lugs during strap changes. The 8mm screw-down crown, referred to as the Alchemical Sun crown, is deliberately oversized and deeply fluted to maximize torque when threading it securely against the case tube gaskets, a critical interaction point for maintaining the 600-meter water resistance.

Sealing the dial from the external environment is a 3mm thick double-domed sapphire crystal, equipped with an inner anti-reflective coating to counteract the mirror effect that occurs when reading a watch underwater at shallow angles. The double-dome geometry ensures that the crystal thickness remains consistent across its entire arc, preventing the optical distortion common in single-domed crystals. Surrounding the crystal is a 120-click mono-directional safety bezel, engineered to provide precise half-minute increments for tracking elapsed bottom time. The brand has transitioned from traditional anodized aluminum to a technical ceramic insert for these models, vastly increasing the surface hardness to resist blunt force impacts and abrasive contact with diving equipment. This ceramic insert is lume-infused, utilizing a manufacturing method where the indices are deeply engraved into the ceramic material and subsequently filled with Super-LumiNova BGW9, creating a permanent, flush luminous application that cannot be easily chipped or worn away through friction.

The dial layout is executed in either matte black or reflex blue, both utilizing a flat, non-reflective base pigment designed to maximize the contrast of the applied luminous material. Unimatic employs a dual-emission Super-LumiNova scheme to segregate vital information in low-light environments. The hour hand, reverse lollipop second hand, and the distinct circular hour markers emit a custom white/orange glow, while the minute hand and the bezel pip utilize BGW09 to emit a bright blue glow, allowing the user to immediately isolate the minute-tracking functions from the general time display. The hands themselves feature a phantom ladder design, where the base of the handset is painted to match the dial color, creating an optical illusion where only the luminous tips appear to float around the dial perimeter. A closed white matte second rail frames the outer edge of the dial for precise synchronization, and a circular date aperture is positioned at six o'clock, maintaining the vertical symmetry of the dial without removing a critical luminous index at the standard three o'clock position.

The Movement

Powering all references in this specific ProDiver line is the Swiss-manufactured Sellita SW200-1 automatic caliber, a highly standardized and robust mechanical tractor known for its ease of serviceability and parts availability. This movement operates at a frequency of 28,800 vibrations per hour, or 4 Hertz, dividing each second into eight distinct mechanical steps. This higher beat rate translates visually to a smoother sweep of the reverse lollipop seconds hand, which is crucial for divers who rely on the continuous motion of the seconds hand as a fundamental indicator that the watch is actively running and has not flooded or seized. The architecture utilizes 26 jeweled bearings to reduce friction at critical pivot points within the gear train, contributing to the movement's long-term durability under harsh physical impacts.

The SW200-1 features a hacking seconds mechanism, a vital function for professional timing instruments that completely arrests the balance wheel when the crown is pulled to the final position. This allows the user to halt the movement entirely and synchronize the precise second with a dive computer, a radio-controlled clock, or a team member's timing device before beginning an operation. The mainspring barrel stores a typical power reserve of 41 hours, providing sufficient energy to maintain the manufacturer's stated accuracy tolerance of ±12 seconds per day even when the watch is left stationary overnight. Winding is achieved bi-directionally via the central rotor, efficiently harvesting kinetic energy from the wearer's wrist movements to keep the mainspring under optimal tension, ensuring consistent amplitude and timekeeping stability across the entire power reserve cycle.

The Strap and Bracelet Options

The baseline strap provided with the U1S-PD6-B and U1S-PD6-RB references is manufactured from Thermoplastic Polyurethane (TPU), an industrial polymer chosen for its specific environmental resistances. Unlike standard silicone, which attracts particulate matter and can tear under heavy strain, or vulcanized rubber, which can degrade when exposed to certain ultraviolet light spectrums and petroleum chemicals, TPU remains structurally inert and highly resilient to saltwater corrosion. The strap utilizes a two-piece architecture with integrated quick-release spring bars, allowing the user to disengage the strap from the drilled lugs without the use of external metal tools. The hardware consists of a heavy-gauge, brushed stainless steel tang buckle that mirrors the finish of the main case body and is deeply engraved with the Unimatic signature.

For the UBK designations, Unimatic includes a brushed solid stainless steel bracelet alongside the standard TPU strap, effectively converting the watch from a dedicated aquatic tool to a heavier, more rigid platform. The bracelet links are machined from solid blocks of 316L stainless steel, matching the exact alloy composition and brushed grain direction of the watch case to ensure visual uniformity. Solid end links are utilized to anchor the bracelet to the case head, filling the entire 22mm lug width precisely to prevent any lateral shifting or structural weakness at the primary connection point. This rigid integration distributes the weight of the dense 600m case evenly around the circumference of the wrist, countering the top-heavy nature inherent in deep-diving watch designs.

Pricing and Availability

The distribution model for these specific Modello Uno ProDiver references is strictly limited, with production capped at exactly 300 individually numbered units for each of the four configurations. The standard models equipped exclusively with the TPU strap, specifically the U1S-PD6-B in black and the U1S-PD6-RB in blue, are positioned at a retail price of $1,820. The premium bundles, designated by the UBK suffix, which include both the solid steel bracelet and the secondary TPU strap, carry a higher retail cost of $1,960.

Each timepiece is packaged and delivered within a proprietary Unimatic tough case, a high-impact polymer container designed to shield the instrument from blunt force trauma and pressure variations during global transit. Included within this utilitarian packaging is a physical warranty card sealed with a unique identification marker that aligns directly with the specific production number engraved into the solid steel case back. The manufacturer backs the mechanical integrity and water resistance of the watches with a standard 24-month worldwide warranty, covering internal caliber defects and structural failures under normal operational parameters.

Technical Specifications

Case: 40mm diameter (41.5mm with bezel), 316L stainless steel, brushed finish, 22mm drilled lugs, 8mm screw-down crown

Movement: Swiss Sellita SW200-1 automatic, 28,800 bph, 26 jewels, hacking seconds, 41-hour typical power reserve

Dial: Matte black or reflex blue, phantom ladder hands, dual Super-LumiNova system (BGW09 and custom white/orange), date at 6 o'clock

Strap: TPU two-piece quick-release strap; UBK bundles include additional solid brushed stainless steel bracelet

Price: $1,820 (TPU strap only) / $1,960 (UBK Premium Bundle)

Reference Number: U1S-PD6-B, U1S-PD6-RB, U1S-PD6-B-UBK, U1S-PD6-RB-UBK

Notes: Limited edition of 300 pieces per reference, individually numbered, 600m/2000ft/60atm water resistance, 3mm double-domed sapphire crystal