Side by side

Fortis Marinemaster M-40vsSeiko Prospex Sea 1970 Heritage Diver's Black Series Limited Edition

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

At a glance

11 of 29 specs differ
Diameter
Marinemaster M-4040mm
Prospex Sea 1970 Heritage Diver's Black Series Limited Edition44mm
Power Reserve
Marinemaster M-4038h
Prospex Sea 1970 Heritage Diver's Black Series Limited Edition50h
Water Resistance
Marinemaster M-40300m
Prospex Sea 1970 Heritage Diver's Black Series Limited Edition200m
MSRP
Marinemaster M-40$3,520
Prospex Sea 1970 Heritage Diver's Black Series Limited Edition$3,300

Full specifications

Case

4 specs
Diameter
40mm
44mm
Lug-to-Lug
49.3mm
Lug Width
21mm
20mm
Water Resistance
300m
200m

Crystal & Dial

4 specs
Crystal Shape
Flat
Curved
AR Coating
Inner
Anti-reflective coating on inner surface
Dial Color
Orange
Black
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

2 specs
Caliber
Sellita SW220-1
8L35
Power Reserve
38h
50h

Pricing

1 specs
MSRP
$3,520
$3,300

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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 1970 Heritage Diver's Black Series Limited Edition

Owners widely praise the Seiko Prospex Sea 1970 Heritage Diver's Black Series Limited Edition for its attractive, well-made design and gorgeous dial, noting its jewel-toned teal color and rippling-water pattern. The bezel action is smooth with a muted sound, and the case and bracelet offer a more comfortable feel than previous iterations. However, multiple owners express disappointment with the accuracy of the 6R movement at its price point, with some noting theirs runs slow, and consider the price too high. The steep rehaut and marker size make the 24-hour numbers difficult to read, and some find the case design makes the watch feel top-heavy despite wearing smaller. Overall, owners rate the Seiko Prospex Sea 1970 Heritage Diver's Black Series Limited Edition highly for its striking dial and refined case design, despite concerns regarding movement accuracy at its price.

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