Side by side

Fortis Marinemaster M-40vsSeiko Prospex Sea

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
Prospex Sea
SeikoProspex Sea
MSRP $795

At a glance

13 of 29 specs differ
Diameter
Marinemaster M-4040mm
Prospex Sea34mm
Power Reserve
Marinemaster M-4038h
Prospex Sea40h
Water Resistance
Marinemaster M-40300m
Prospex Sea200m
MSRP
Marinemaster M-40$3,520
Prospex Sea$795

Full specifications

Case

5 specs
Diameter
40mm
34mm
Thickness
13mm
8.7mm
Lug-to-Lug
40.8mm
Lug Width
21mm
16mm
Water Resistance
300m
200m

Crystal & Dial

3 specs
AR Coating
Inner
Anti-reflective coating on inner surface
Dial Color
Orange
Black
Lume
None
LumiBrite on hands and index(es)

Movement

4 specs
Caliber
Sellita SW220-1
6N01
Type
Automatic
Quartz
Power Reserve
38h
40h
Jewels
26
25

Pricing

1 specs
MSRP
$3,520
$795

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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 Prospex Sea

Owners widely praise the Seiko Prospex Sea for its excellent value, robust build, and superb lume, with many appreciating its comfortable wearability due to its case shape and lug-to-lug distance. Reviewers consistently highlight its impressive finishing and classic dive watch design, often noting the bright LumiBrite lume. Some owners find the watch to be large, thick, and heavy, while others consider it the perfect size, indicating a split opinion on wearability for smaller wrists. The power reserve from some movements is noted as less than newer variants, and the clasp quality receives mixed feedback. Overall, owners and reviewers rate the Seiko Prospex Sea highly for its exceptional finishing and value proposition in the dive watch market.

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