Side by side

Fortis Marinemaster M-40vsSeestern S456 GMT

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
S456 GMT
SeesternS456 GMT
MSRP $299

At a glance

15 of 29 specs differ
Diameter
Marinemaster M-4040mm
S456 GMT41mm
Power Reserve
Marinemaster M-4038h
S456 GMT41hh
Water Resistance
Marinemaster M-40300m
S456 GMT200m
MSRP
Marinemaster M-40$3,520
S456 GMT$299

Full specifications

Case

7 specs
Category
Diver
GMT
Diameter
40mm
41mm
Lug-to-Lug
49mm
Lug Width
21mm
20mm
Material
Stainless Steel
316L Stainless Steel
Finish
Brushed and polished
Brushed + Polished
Water Resistance
300m
200m

Crystal & Dial

2 specs
Dial Color
Orange
Sunray style, applied and Diamond cut Indices, C1 lume
Lume
None
C1

Movement

5 specs
Caliber
Sellita SW220-1
Seiko NH34
Beat Rate
28,800 vph
3 vph
Power Reserve
38h
41hh
Jewels
26
24
Complications
None
GMT

Pricing

1 specs
MSRP
$3,520
$299

Follow this matchup

Get a note when Fortis Marinemaster M-40 vs Seestern S456 GMT gets more votes, a community discussion, or a price drop. No account needed.

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.

Seestern S456 GMT

Owners widely praise the Seestern S456 GMT for its exceptional value and finishing that exceeds expectations, with one owner noting its accuracy surpasses that of their Seiko 5. The dial displays a pearl-like rainbow effect. Some owners would prefer a bidirectional bezel over the current unidirectional one. The Seestern S456 GMT features an NH34 movement, a 39.5mm case, sapphire crystal, and an adjustable clasp. On balance, owners rate the Seestern S456 GMT highly for its impressive finishing and value proposition at its price point.

From video reviewers

The watch features stunning, detailed finishing that is difficult to top. Reviewers did not reach a consensus on any weaknesses.

Keep exploring

More watches worth a look

Matched to the watches above on size, movement, style and price — microbrands first. Open any one to dig in.

Adjacent matchups

People also compared

Comparisons nearby in the catalog — alternatives to the watches above paired against the matchup.