Side by side

Fortis Marinemaster M-40vsSeiko 5 Sports SKX series

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
5 Sports SKX series
Seiko5 Sports SKX series
MSRP $350

At a glance

12 of 29 specs differ
Diameter
Marinemaster M-4040mm
5 Sports SKX series38mm
Power Reserve
Marinemaster M-4038h
5 Sports SKX series41h
Water Resistance
Marinemaster M-40300m
5 Sports SKX series100m
MSRP
Marinemaster M-40$3,520
5 Sports SKX series$350

Full specifications

Case

5 specs
Diameter
40mm
38mm
Thickness
13mm
12.1mm
Lug-to-Lug
44.2mm
Lug Width
21mm
20mm
Water Resistance
300m
100m

Crystal & Dial

3 specs
Crystal
Sapphire
Hardlex
Dial Color
Orange
Black
Lume
None
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
Sellita SW220-1
4R36
Power Reserve
38h
41h
Jewels
26
24

Pricing

1 specs
MSRP
$3,520
$350

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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.

Seiko 5 Sports SKX series

The Seiko 5 Sports SKX series is widely praised for its value, robust build, and powerful lume, with owners appreciating its comfortable bracelets and improved movement featuring hacking and hand-winding. Some owners find the original SKX models heavy and bulky, while others praise their ruggedness and iconic dive watch design. Reviewers note the 38mm models offer great value at around €350 and are exemplary gateway watches, though their 100m water resistance without a screw-down crown makes them unsuitable for diving. The Seiko 5 Sports SKX series is seen as a decent watch, especially under £200, but lacks the tool watch capabilities of the original SKX, missing a screw-down crown, bezel pip, and ISO rating. On balance, owners and reviewers rate the Seiko 5 Sports SKX series well for its blend of value, improved movement, and tool-watch aesthetic, despite some missing dive certifications.

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