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 $315

At a glance

13 of 29 specs differ
Diameter
Marinemaster M-4040mm
5 Sports SKX series28mm
Power Reserve
Marinemaster M-4038h
5 Sports SKX series40h
Water Resistance
Marinemaster M-40300m
5 Sports SKX series100m
MSRP
Marinemaster M-40$3,520
5 Sports SKX series$315

Full specifications

Case

6 specs
Category
Diver
Sport
Diameter
40mm
28mm
Thickness
13mm
11.2mm
Lug-to-Lug
33.1mm
Lug Width
21mm
14mm
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
2R06
Power Reserve
38h
40h
Jewels
26
21

Pricing

1 specs
MSRP
$3,520
$315

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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

Owners widely praise the Seiko 5 Sports SKX series for its iconic dive watch design, robust build, and excellent value, with many appreciating its timeless styling and tool-like character. The movement, while basic, is noted as offering hacking and hand-winding capabilities, and accuracy varies, with many owners reporting +/-5 to 10 seconds per day despite the movement's potential for +/-40 seconds. Some owners find the original SKX models heavier and bulkier than newer iterations, while others critique the lack of a screw-down crown and ISO rating on the newer Seiko 5 Sports SKX series, deeming it less of a serious tool watch. Overall, owners rate the Seiko 5 Sports SKX series highly for its enduring design and value proposition as a robust, everyday watch.

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