Side by side

Marathon Steel Navigator SSNAV AutovsSeiko Prospex Sea

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

Steel Navigator SSNAV Auto
MarathonSteel Navigator SSNAV Auto
MSRP $1,300
Prospex Sea
SeikoProspex Sea
MSRP $625

At a glance

13 of 29 specs differ
Diameter
Steel Navigator SSNAV Auto41mm
Prospex Sea43.8mm
Power Reserve
Steel Navigator SSNAV Auto40h
Prospex Sea41h
Water Resistance
Steel Navigator SSNAV Auto60m
Prospex Sea200m
MSRP
Steel Navigator SSNAV Auto$1,300
Prospex Sea$625

Full specifications

Case

7 specs
Category
Pilot
Diver
Diameter
41mm
43.8mm
Thickness
11.5mm
12.8mm
Lug-to-Lug
48mm
48.7mm
Lug Width
20mm
22mm
Material
316L Stainless Steel
Stainless Steel
Water Resistance
60m
200m

Crystal & Dial

2 specs
AR Coating
Inner
Anti-reflective coating on inner surface
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Sellita SW200-1
4R35
Power Reserve
40h
41h
Jewels
25
23

Pricing

1 specs
MSRP
$1,300
$625

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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.

Marathon Steel Navigator SSNAV Auto

The Marathon Steel Navigator SSNAV Auto is praised for its high-accuracy quartz movement, with owners noting its comfort and reliable performance. Reviewers highlight its functional tool-watch appeal, featuring a sandblasted steel case, tritium tubes for constant low-light visibility, and 100-meter water resistance. One owner finds the 41mm case runs a bit small. The Marathon Steel Navigator SSNAV Auto utilizes an ETA F06.412 quartz movement with a claimed accuracy of +/- 10 seconds per year and includes a GMT bidirectional bezel. Overall, owners and reviewers rate the Marathon Steel Navigator SSNAV Auto highly for its comfortable wear and dependable, high-accuracy quartz movement.

Seiko Prospex Sea

The Seiko Prospex Sea is widely praised for its excellent value, solid build quality, and comfortable wearability, with many models featuring impressive lume and attractive dials. Owners and reviewers highlight the modern upgrades on classic designs, such as drilled lugs and reliable movements with hacking and hand-winding capabilities. Some models are noted for their refined case finishing and scratch resistance. Accuracy figures vary, with one owner reporting approximately 4 seconds fast per day, while others find the movements offer good performance for the price. Concerns raised by owners and reviewers include clasps that can feel generic or cheap, and lug widths that some find disproportionate to the case size on certain models. The thickness and weight of some Prospex Sea watches are also noted as substantial. The GMT function on specific models is considered secondary and difficult to read for true travel purposes.

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