Side by side

Fortis Marinemaster M-40vsSeiko Prospex Sea Save the Ocean Special Edition

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

At a glance

12 of 29 specs differ
Diameter
Marinemaster M-4040mm
Prospex Sea Save the Ocean Special Edition45mm
Power Reserve
Marinemaster M-4038h
Prospex Sea Save the Ocean Special Edition41h
Water Resistance
Marinemaster M-40300m
Prospex Sea Save the Ocean Special Edition200m
MSRP
Marinemaster M-40$3,520
Prospex Sea Save the Ocean Special Edition$625

Full specifications

Case

5 specs
Diameter
40mm
45mm
Thickness
13mm
13.2mm
Lug-to-Lug
47.7mm
Lug Width
21mm
22mm
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, index(es) and bezel

Movement

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

Pricing

1 specs
MSRP
$3,520
$625

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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 Save the Ocean Special Edition

The Seiko Prospex Sea Save the Ocean Special Edition is widely praised for its attractive, unique, and textured dials, often described as having a "Grand Seiko feel" at a more accessible price point, with specific mentions of wave patterns, lagoon hues, and manta ray motifs. Owners appreciate the smooth bezel operation and satisfactory lume. Accuracy figures vary, with one owner reporting +5 seconds per day, while another notes a range from +1/+2 to about -6 seconds per day. The 6R35 movement offers a 70-hour power reserve, and some models feature sapphire crystals. Criticisms include a desire for exhibition casebacks and concerns about the quality and security of the stamped metal clasps and bracelets, which are frequently described as rattly or underwhelming, though this is noted as a common Seiko trait. Some owners are split on the number of Save the Ocean variations and dislike the cyclops magnifier.

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