Side by side

Fortis Marinemaster M-40vsSeiko Prospex SPEEDTIMER Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition

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

At a glance

15 of 29 specs differ
Diameter
Marinemaster M-4040mm
Prospex SPEEDTIMER Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition42mm
Power Reserve
Marinemaster M-4038h
Prospex SPEEDTIMER Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition40h
Water Resistance
Marinemaster M-40300m
Prospex SPEEDTIMER Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition100m
MSRP
Marinemaster M-40$3,520
Prospex SPEEDTIMER Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition$2,400

Full specifications

Case

6 specs
Category
Diver
Chronograph
Diameter
40mm
42mm
Thickness
13mm
12.9mm
Lug-to-Lug
49.6mm
Lug Width
21mm
20mm
Water Resistance
300m
100m

Crystal & Dial

4 specs
Crystal Shape
Flat
Curved
AR Coating
Inner
Super-clear coating
Dial Color
Orange
Black
Lume
None
LumiBrite on hands and index(es)

Movement

4 specs
Caliber
Sellita SW220-1
5X83
Type
Automatic
Quartz
Power Reserve
38h
40h
Jewels
26
14

Pricing

1 specs
MSRP
$3,520
$2,400

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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 Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition

The Prospex SPEEDTIMER Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition is praised for its retro design, balanced 42mm case, good finishing, and sapphire crystal. It is powered by the calibre 8R48, featuring a column wheel and vertical clutch, and offers 100m water resistance. Some find its 45-hour power reserve short compared to modern alternatives, and the date window placement is a point of discussion. The solar-powered variant is noted for its compact proportions and character, though some desire thinner cases and improved bracelet micro-adjustment. Overall, owners and reviewers appreciate the SPEEDTIMER's vintage-inspired aesthetics and solid build, with critiques focusing on power reserve and minor functional details.

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