The UNIMATIC Modello Quattro U4-GMT, reference UWK-U4-GMT, is a 40 mm automatic GMT watch limited to 300 individually numbered pieces. Its official listing currently marks it sold out. UNIMATIC specifies a Seiko NH34A movement, a fixed 24-hour bezel, a 300 m water-resistance rating and a charcoal-gray quick-release TPU strap. These are manufacturer specifications; no independent wear or performance test of this reference is available here.
What the UWK-U4-GMT is
UNIMATIC describes the UWK-U4-GMT as a GMT military watch made in Italy. The reference is the original 300-piece Modello Quattro U4-GMT, not a catch-all name for every U4-GMT variant. Its design pairs a matte black dial and fixed, deeply etched 24-hour bezel with a charcoal-gray TPU strap.
The official product page lists the 300-piece edition as sold out. Stock can change, so check the UNIMATIC product page for current status rather than assuming it is available or quoting an unverified price.
How the NH34A GMT works
UNIMATIC specifies an automatic Seiko NH34A with a GMT function, hacking seconds, 24 jewels and a 41-hour power reserve. The GMT hand is the additional 24-hour hand: read its hollow arrow tip against the bezel’s 24-hour scale to track a second time zone. The dial’s central hour and minute hands remain the primary local-time display, while the date sits at 6 o’clock.
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- BLUE DIAL: this handsome men’s watch features a striking deep blue dial with luminous dial indicator hands and markers and date calendar to keep you organized
- BLUE & BLACK BEZEL: with a 24-hour bezel and easy-to-read fourth hand, this GMT watch helps you keep time as you travel
- DURABLE UTILITY: these versatile men’s wrist watches feature a 42.5mm stainless steel watch case and bracelet, for a classic, timeless look.
- WATER-RESISTANT: this rugged sports watch is water-resistant up to 100 meters
- 4R34 CALIBER: equipped with the reliable 4R34 caliber, these automatic watches for men ensure the most accurate in self winding timekeeping, with 41 hours of reserve power and manual winding option
The technical sheet gives a stated accuracy of -20/+40 seconds per day and a beat rate of 21,600 beats per hour. These are manufacturer figures, not results from a test of this watch. UNIMATIC lists hacking seconds, which means the seconds hand stops when the crown is pulled to set the time.
Case, crystal and water-resistance specifications
| Specification | UNIMATIC listing |
|---|---|
| Case diameter | 40 mm |
| Thickness | 13.8 mm |
| Height | 49 mm |
| Case material and finish | Brushed 316 stainless steel |
| Crown and bezel | 8 mm screw-down crown; fixed monoblock bezel with deeply etched 24-hour scale |
| Crystal | 2.8 mm flat sapphire with inner anti-reflective coating |
| Water resistance | 300 m / 30 ATM / 1,000 ft, stated by UNIMATIC as individually tested |
The water-resistance figure is the brand’s stated rating, not a guarantee of performance in every real-world situation. Follow UNIMATIC’s care guidance and have the watch’s seals checked as appropriate before exposing it to water.
Dial details and strap fit
The dial is matte black, with white Super-LumiNova C1 and cool-gray details on the seconds rail and dial trims. UNIMATIC lists black ladder-style phantom hour and minute hands, a reverse-lollipop seconds hand and a 24-hour hand with a hollow arrow tip. The technical sheet identifies the bezel as fixed, so its 24-hour scale is a reference for reading the GMT hand rather than a rotating timing bezel.
Rank #2
- GMT Swiss Watch: The practical GMT function makes it possible to display two time zones simultaneously thanks to an additional hand that makes one complete revolution in 24 hours and uses a bezel graduated over 24 hours to indicate a second time zone.
- Movement: Automatic Mido Caliber 80 with Navichron balance spring which reduces magnetic interference and is remarkably robust against impacts and the effects of time. This caliber ensures exceptional autonomy of up to 80 hours.
- Water Resistance: This Swiss-made MIDO timepiece is capable of withstanding pressures of up to 20 bar (200 m/660 ft), and equipped with a screw-down crown, this watch offers optimal protection against water.
- Case Size: 44mm - Case Thickness: 13.38mm. Stainless steel case with blue ceramic bezel and Sapphire crystal with double sided anti-reflection treatment - Lug Width 22mm
- Strap: Tapered, Blue Fabric Strap with Pin Buckle
The included two-piece TPU strap is charcoal gray, quick-release and tapered from 22 mm at the lugs to 20 mm at the buckle. The case has 22 mm drilled lugs. UNIMATIC’s FAQ states, “All UNIMATIC watches have a lug width of 22mm.” A replacement strap should therefore be 22 mm wide at the lugs; also confirm quick-release pin compatibility, taper and strap length on the individual listing. No third-party strap fit has been tested for this article.
How it differs from other U4-GMT editions
The shared U4-GMT name appears on separate editions with different specifications. Their edition sizes, dials and straps should not be attributed to the UWK-U4-GMT.
| Reference | Edition and distinguishing details |
|---|---|
| UWK-U4-GMT | 300 pieces; matte black dial; charcoal-gray quick-release TPU strap. The product page currently marks it sold out. |
| U4-GMT-AEB | 250-piece Impronte edition; black dial; supplied with two NATO straps. |
| U4-GMT-MMC | 100-piece Morgan collaboration; blue dial; supplied with two leather straps. |
| U4-GMT-EMJDM | A separate Japan-exclusive E. Marinella collaboration announced in a UNIMATIC press release dated October 2, 2026; availability was not established in the announcement materials. |
These are distinct references, not color or strap options for the original watch. The available information does not establish a single best choice: that depends on whether you prefer the original’s TPU strap and black dial, the AEB’s NATO setup, or the MMC’s blue dial and leather straps.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
