Side by side

Fortis Marinemaster M-40vsTudor Black Bay One 31

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

Marinemaster M-40
FortisMarinemaster M-40
MSRP $3,520
Black Bay One 31
TudorBlack Bay One 31
MSRP $4,600

At a glance

12 of 29 specs differ
Diameter
Marinemaster M-4040mm
Black Bay One 3131mm
Power Reserve
Marinemaster M-4038h
Black Bay One 3150h
Water Resistance
Marinemaster M-40300m
Black Bay One 31100m
MSRP
Marinemaster M-40$3,520
Black Bay One 31$4,600

Full specifications

Case

7 specs
Diameter
40mm
31mm
Thickness
13mm
9.5mm
Lug-to-Lug
46mm
Lug Width
21mm
17mm
Finish
Brushed and polished
Polished + Satin
Water Resistance
300m
100m
Caseback
Solid
Solid screw-down

Crystal & Dial

1 specs
Dial Color
Orange
Anthracite

Movement

3 specs
Caliber
Sellita SW220-1
MT5201
Power Reserve
38h
50h
Jewels
26
25

Pricing

1 specs
MSRP
$3,520
$4,600

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What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

Fortis Marinemaster M-40

Owners praise the Fortis Amber Orange for its gorgeous appearance and strong wrist presence, noting its crazy lume and 70-hour power reserve. The Doxa SUB 300T, described as having a superb, eccentric design with a highly legible dial and functional no-decompression bezel, uses an ETA 2824-2 movement. However, the SUB 300T's 42.5mm case wears large and its 14mm thickness is not ideal for dress shirts, though it boasts 1,200m water resistance. On balance, owners appreciate the Fortis Amber Orange for its striking aesthetics and impressive lume.

Tudor Black Bay One 31

Owners widely report the Tudor Black Bay One 31's polished case and bracelet scratch easily, though its wearability under gloves and robust movement are praised. Some desire more micro-adjustment options on the clasp, and a lack of contrast between the silver dial and hands is noted. The 31mm size may be a consideration for daily wear due to its 50-hour power reserve. On balance, owners and reviewers appreciate the Tudor Black Bay One 31 for its comfortable wearability and robust movement, despite concerns about case scratching and clasp adjustability.

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