Side by side

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

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

At a glance

12 of 29 specs differ
Diameter
Marinemaster M-4040mm
Prospex Marinemaster Marinemaster 1965 Heritage Diver's Watch39.5mm
Power Reserve
Marinemaster M-4038h
Prospex Marinemaster Marinemaster 1965 Heritage Diver's Watch45h
Water Resistance
Marinemaster M-40300m
Prospex Marinemaster Marinemaster 1965 Heritage Diver's Watch200m
MSRP
Marinemaster M-40$3,520
Prospex Marinemaster Marinemaster 1965 Heritage Diver's Watch$2,800

Full specifications

Case

5 specs
Diameter
40mm
39.5mm
Thickness
13mm
12.3mm
Lug-to-Lug
47.2mm
Lug Width
21mm
20mm
Water Resistance
300m
200m

Crystal & Dial

4 specs
Crystal Shape
Flat
Box
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
6L37
Power Reserve
38h
45h

Pricing

1 specs
MSRP
$3,520
$2,800

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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 Marinemaster Marinemaster 1965 Heritage Diver's Watch

The Seiko Prospex Marinemaster 1965 Heritage Diver's Watch is praised for its faithful re-creation of the 62MAS design, with reviewers noting improved wearability due to smaller case sizes (38mm to 40mm) and updated bracelets. Specific models feature a stainless steel case with super-hard coating, ceramic bezel, and a tool-free extension system on the bracelet. Accuracy figures vary, with one model rated at -5/+10 seconds per day and another at -10/+15 seconds per day, powered by movements like the Caliber 8L45 or 6L37 offering 72-hour or 46-hour power reserves respectively. Some reviewers point out drawbacks such as an unsigned winding crown, a lack of tool-free micro-adjust on the clasp for certain models, and a secondary GMT function on one variant. The price point, ranging from $2,800 to $3,600, is considered high by some, especially when compared to other Seiko or Grand Seiko offerings.

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