Side by side

Fortis Marinemaster M-40vsSeiko Prospex Sea 1965 Heritage Diver's Watch

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

10 of 29 specs differ
Diameter
Marinemaster M-4040mm
Prospex Sea 1965 Heritage Diver's Watch40mm
Power Reserve
Marinemaster M-4038h
Prospex Sea 1965 Heritage Diver's Watch72h
Water Resistance
Marinemaster M-40300m
Prospex Sea 1965 Heritage Diver's Watch300m
MSRP
Marinemaster M-40$3,520
Prospex Sea 1965 Heritage Diver's Watch$1,300

Full specifications

Case

2 specs
Lug-to-Lug
46.4mm
Lug Width
21mm
20mm

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

3 specs
Caliber
Sellita SW220-1
6R55
Power Reserve
38h
72h
Jewels
26
24

Pricing

1 specs
MSRP
$3,520
$1,300

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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 1965 Heritage Diver's Watch

The Seiko Prospex Sea 1965 Heritage Diver's Watch is praised for its refined engineering and updated features, including a 300m water resistance and a 72-hour power reserve from the Caliber 6R55 movement in a 40mm case. Owners note its better build quality and interesting finishing with a mix of polished and brushed surfaces. The "Tranquil Teal" variant features a jewel-toned dial with a rippling-water pattern. However, some owners consider the price too high, and concerns exist regarding the accuracy of the 6R movements, with some reporting theirs run slow. One review notes a reflective dial that impacts legibility. On balance, owners and reviewers appreciate the Seiko Prospex Sea 1965 Heritage Diver's Watch for its refined design and improved specifications over previous generations, despite some reservations about movement accuracy and price.

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