Side by side

Fortis Marinemaster M-40vsSeiko Prospex Sea The Black 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
Prospex Sea The Black Series
SeikoProspex Sea The Black Series
MSRP $765

At a glance

12 of 29 specs differ
Diameter
Marinemaster M-4040mm
Prospex Sea The Black Series45mm
Power Reserve
Marinemaster M-4038h
Prospex Sea The Black Series41h
Water Resistance
Marinemaster M-40300m
Prospex Sea The Black Series200m
MSRP
Marinemaster M-40$3,520
Prospex Sea The Black Series$765

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
$765

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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 The Black Series

The Seiko Prospex Sea The Black Series is widely praised for its impressive value and compelling design elements. Reviewers highlight the SLA073's cave-diving-inspired dial, high-quality bracelet, and the robust 8L35 movement, calling it a standout release. The SRPE33 and SRPE39 models are noted for their attractive price, manta ray decorated dials, and excellent LumiBrite lume, though bezel alignment can be inconsistent. The SNJ029 is celebrated for its dynamic, colorful aesthetic, solar charging, and comfortable strap, making it ideal for outdoor adventures. Overall, the consensus is that Seiko Prospex Sea The Black Series models offer excellent value, with specific models lauded for their unique dials, quality finishing, and practical features like solar charging.

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