Side by side

Fortis Marinemaster M-40vsGrand Seiko STGK031

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
STGK031
Grand SeikoSTGK031
MSRP $6,600

At a glance

12 of 29 specs differ
Diameter
Marinemaster M-4040mm
STGK03130mm
Power Reserve
Marinemaster M-4038h
STGK03150h
Water Resistance
Marinemaster M-40300m
STGK031100m
MSRP
Marinemaster M-40$3,520
STGK031$6,600

Full specifications

Case

6 specs
Category
Diver
Dress
Diameter
40mm
30mm
Thickness
13mm
10.5mm
Lug-to-Lug
36.2mm
Lug Width
21mm
15mm
Water Resistance
300m
100m

Crystal & Dial

2 specs
AR Coating
Inner
Yes
Dial Color
Orange
Black

Movement

3 specs
Caliber
Sellita SW220-1
9S27
Power Reserve
38h
50h
Jewels
26
25

Pricing

1 specs
MSRP
$3,520
$6,600

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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.

Grand Seiko STGK031

Grand Seiko STGK031 owners widely praise its subtle, light pink dial that shifts to appear white or silver depending on lighting, its refined 30mm case size, and its simple elegance. Some find the 30mm sizing perfect for wearability, with one owner noting it is ideal for those who find 38mm watches too large. The Zaratsu polishing is also a noted strength. However, the Calibre 9S27 movement has a 50-hour power reserve and an accuracy range of +8 to -3 seconds per day, which some consider modest for the price. On balance, owners and reviewers rate the Grand Seiko STGK031 highly for its versatile dial and refined 30mm case.

From video reviewers

The 50-hour power reserve of the Calibre 9S27 movement is a shared strength. The 36mm lug-to-lug measurement is a weakness. Reviewers disagreed on the premium feel of the polished stainless steel case and bracelet compared to Zaratsu polishing.

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