Side by side

Fortis Marinemaster M-40vsSeiko Prospex SPEEDTIMER Mechanical

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 SPEEDTIMER Mechanical
SeikoProspex SPEEDTIMER Mechanical
MSRP $995

At a glance

14 of 29 specs differ
Diameter
Marinemaster M-4040mm
Prospex SPEEDTIMER Mechanical39.5mm
Power Reserve
Marinemaster M-4038h
Prospex SPEEDTIMER Mechanical72h
Water Resistance
Marinemaster M-40300m
Prospex SPEEDTIMER Mechanical200m
MSRP
Marinemaster M-40$3,520
Prospex SPEEDTIMER Mechanical$995

Full specifications

Case

6 specs
Category
Diver
Chronograph
Diameter
40mm
39.5mm
Thickness
13mm
12mm
Lug-to-Lug
44.5mm
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 and index(es)

Movement

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

Pricing

1 specs
MSRP
$3,520
$995

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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 SPEEDTIMER Mechanical

The Seiko Prospex SPEEDTIMER Mechanical is praised for its visually appealing design and comfortable wearability, with owners frequently using its chronograph function for daily tasks. Reviewers note its clean dial layout and LumiBrite treated hands and markers, and one source highlights the 72-hour power reserve of the 6R55 movement. However, some owners criticize its chronograph functionality and the 24-hour subdial. On balance, owners and reviewers rate the Seiko Prospex SPEEDTIMER Mechanical highly for its daily usability and refined aesthetics.

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