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This is a specification-led comparison, not a report of wearing or testing the watches. Dimensions can help frame a fit decision, but they cannot tell you how either watch will feel on your wrist.
| # | Preview | Product | Price | |
|---|---|---|---|---|
| 1 |
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Tudor Heritage Black Bay GMT Stainless Steel Automatic Mens Watch M79830RB-0001 | $4,650.00 | Buy on Amazon |
| 2 |
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Tudor GMT 58 Black Bay | $5,449.98 | Buy on Amazon |
| 3 |
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TUDOR Black Bay 58 GMT | $5,550.00 | Buy on Amazon |
| 4 |
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Tudor Black Bay Automatic Black Dial GMT Pepsi Bezel Men's Watch 79830RB-0002 | $4,900.00 | Buy on Amazon |
| 5 |
|
Tudor Black Bay Automatic Chronometer Black Dial Men's Watch M79833MN-0001 | $7,499.99 | Buy on Amazon |
How the Black Bay GMT and Black Bay Pro differ
| Specification | Black Bay GMT Opaline | Black Bay Pro Opaline |
|---|---|---|
| Official reference | M79830RB-0012 | M79470-0004 |
| Case diameter | 41 mm | 39 mm |
| Case thickness | 14.6 mm | 14.6 mm |
| Lug width | 22 mm | 20 mm |
| Bezel | Bidirectional rotating 24-hour bezel with burgundy-and-blue aluminum insert | Fixed satin-brushed steel bezel with 24-hour graduation |
| Dial and GMT hand | Domed opaline dial with galvanic finish; red 24-hour hand | Domed opaline dial; yellow 24-hour hand |
| Movement and power reserve | MT5652; approximately 70 hours | COSC MT5652; approximately 70 hours |
| Water resistance | 200 m | 200 m |
| Listed configuration | Black fabric strap with burgundy band | Riveted steel bracelet with T-fit clasp |
These are TUDOR’s specifications for the Black Bay GMT M79830RB-0012 and Black Bay Pro M79470-0004. They establish listed dimensions and features, not independent measurements or a verdict on comfort, legibility or performance.
How does the Black Bay Pro GMT work?
The Pro’s yellow 24-hour hand tracks reference time against the fixed 24-hour scale on the steel bezel. Its local-hour hand can be advanced or moved back in one-hour increments, so you can adjust local time when travelling without shifting the GMT hand from its reference-time reading. TUDOR describes the MT5652 as a movement with a built-in GMT function developed for the Black Bay Pro.
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#1 Best Overall
- 41mm steel case with polished and satin finish
- Bidirectional rotatable bezel in steel with 24-hour graduated anodised aluminium disc
- Self-winding mechanical movement with 70 hour power reserve
The Black Bay GMT uses a different workflow: its red 24-hour hand reads reference time, while the bidirectional rotating 24-hour bezel can be repositioned to support another time-zone reading. The bezel therefore provides an adjustable reference for additional time-zone tracking; the Pro’s bezel remains fixed and its jumping local-hour hand is the travel-adjustment feature.
Which case size and strap setup should you consider?
Case dimensions and wrist fit
The Pro is 2 mm smaller in stated diameter, at 39 mm versus 41 mm, but both watches are listed at 14.6 mm thick. Their lug widths also differ: 20 mm on the Pro and 22 mm on the GMT. The narrower Pro may be the more appealing specification for someone seeking a smaller-diameter watch, but the numbers alone cannot establish which one sits better on a particular wrist. Try each on if fit is decisive.
Rank #2
- Tudor Black Bay 58 GMT "Coke" Automatic 39mm Black Dial Men's Watch M7939G1A0NRU-0001
Bracelet, fabric strap and compatibility
The cited Pro reference is listed with a riveted steel bracelet and T-fit clasp; the cited GMT reference comes on a black fabric strap with a burgundy band. These are the configurations attached to those references in TUDOR’s product information, not a claim that no other configuration or regional availability exists. When considering a replacement strap, match the lug width—20 mm for the Pro or 22 mm for the GMT—and check that the end shape suits the case.
What do the watches share?
Both references use TUDOR’s MT5652 movement family, are specified with an approximately 70-hour power reserve and carry a 200 m water-resistance rating. TUDOR calls the reserve “weekend-proof”; that is the manufacturer’s description, not an independent power-reserve test. These common specifications are useful context, but they do not distinguish the watches as clearly as the bezel design, local-hour adjustment, case diameter and supplied strap or bracelet.
Rank #3
- Tudor Black Bay 58 GMT "Coke" Automatic Black Dial Men's Watch M7939G1A0NRU-0002
US suggested retail prices and configuration caveat
When accessed in 2026, TUDOR’s US product pages listed a suggested retail price of $5,075 for the Black Bay Pro Opaline M79470-0004 on its bracelet, and TUDOR’s US product-family listing showed $4,925 for the Black Bay GMT M79830RB-0012 on its fabric strap. These are not bracelet-to-bracelet or strap-to-strap matched prices, and TUDOR reserves the right to change prices and models. Check the current US listing and exact configuration before using either figure to compare cost.
Quick Recap
Best Value
- Tudor Black Bay GMT S&G Automatic Chronometer Black Dial Men's Watch M79833MN-0001
Rank #4
- Tudor Black Bay Automatic Black Dial GMT Pepsi Bezel Men's Watch 79830RB-0002
Which one makes more sense for you?
- Choose the Black Bay GMT Opaline for the listed rotating-bezel approach: it has a 41 mm case, a red reference-time hand and a bidirectional 24-hour bezel that can be repositioned for another time-zone reading.
- Choose the Black Bay Pro Opaline for the travel-time adjustment: its 39 mm case, fixed 24-hour bezel and jumping local-hour hand let you change local time in one-hour steps while retaining the GMT hand’s reference-time reading.
- Compare exact configurations, not just model names: the references described here are supplied differently, and their lug widths are not interchangeable assumptions for strap shopping.
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.
