Black Bay Pro

Ref. M79470

Case diameter: 39 mm; Manufacturer spec
Lug-to-lug: 47.2 mm; Measured in a published review
Thickness: 14.6 mm; Measured in a published review
Lug width: 20 mm; Measured in a published review

Retail price $5,075 (US, Oct 2026)

Your wristIdeal fit

Wrist flat: 55.1 mmLug-to-lug: 47.2 mm

How the Black Bay Pro wears

Its lugs add 8.2 mm to the 39 mm case, close to the 7.1 mm typical across the almanac, so its diameter is a fair guide to how it wears.

On our fit model it sits best on wrists from 6.5" to 7.75" (16.5–19.7 cm); below 6.5" the lugs start to reach the edge of the wrist.

At 14.6 mm thick it is thicker than 100% of the 24 other gmt watches we've measured, so expect it to sit tall on the wrist.

Its 20 mm lug width is one of the most common strap sizes; 104 other watches here share it, so aftermarket straps are easy to find.

Will the Black Bay Pro fit your wrist?

With a 47.2 mm lug-to-lug, here is how it wears across common wrist sizes. We estimate the flat top of each wrist from its circumference; measure yours for a closer answer in the fit finder.

Wrist	Flat width (est.)	Fit
6"	47.2 mm	Lugs overhang
6.5"	51.2 mm	Ideal fit
7"	55.1 mm	Ideal fit
7.5"	59.1 mm	Ideal fit
8"	63 mm	Wears small

Specifications

Reference: M79470
Collection: Black Bay Pro
Status: In production
Introduced: 2022
Case material: stainless steel
Crystal: sapphire
Water resistance: 200 m
Bezel: fixed 24-hour graduated, satin-brushed steel
Dial: black
Strap / bracelet: riveted steel bracelet, T-fit clasp
Style: GMT, Field

Movement

Caliber: Tudor MT5652
Type: automatic
Power reserve: 70 hours
Frequency: 28,800 vph (4 Hz)
Jewels: 28
Accuracy: COSC

Takes 20 mm straps. See other 20 mm watches and straps.

Watches that wear the same size

Other watches within 1.5 mm of its lug-to-lug.

Same 20 mm lug width

All 20 mm watches

These take the same straps as the Black Bay Pro.