Side by side

Marathon Steel Navigator SSNAV-D AutovsSeiko Prospex Sea

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

Steel Navigator SSNAV-D Auto
MarathonSteel Navigator SSNAV-D Auto
MSRP $1,400
Prospex Sea
SeikoProspex Sea
MSRP $900

At a glance

12 of 29 specs differ
Diameter
Steel Navigator SSNAV-D Auto41mm
Prospex Sea41mm
Power Reserve
Steel Navigator SSNAV-D Auto40h
Prospex Sea70h
Water Resistance
Steel Navigator SSNAV-D Auto60m
Prospex Sea200m
MSRP
Steel Navigator SSNAV-D Auto$1,400
Prospex Sea$900

Full specifications

Case

5 specs
Category
Pilot
Diver
Thickness
11mm
12.3mm
Lug-to-Lug
48mm
46.9mm
Material
316L Stainless Steel
Stainless Steel
Water Resistance
60m
200m

Crystal & Dial

3 specs
Crystal Shape
Flat
Curved
AR Coating
Inner
Anti-reflective coating on inner surface
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Sellita SW220-1
6R35
Power Reserve
40h
70h
Jewels
25
24

Pricing

1 specs
MSRP
$1,400
$900

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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-D Auto

The Marathon Steel Navigator SSNAV-D Auto is praised for its durable construction, featuring a sandblasted steel case with improved lugs, a bi-directional bezel with excellent action, and 100m water resistance. Owners appreciate the constant visibility provided by self-illuminating tritium gas tubes and the precision of its ETA F06.412 quartz movement, which offers accuracy to about 10 seconds per year. The watch includes a GMT bezel for dual timekeeping and a synthetic sapphire crystal. Overall, owners and reviewers rate the Marathon Steel Navigator SSNAV-D Auto highly for its robust tool-watch design and reliable tritium illumination.

Seiko Prospex Sea

Owners widely praise the Seiko Prospex Sea for its excellent lume, robust build, and value, with many highlighting the comfortable 4 o'clock crown and reliable movements. Reviewers note impressive case finishing and attractive dials, with specific models lauded for their gradient blue designs and smooth bezel actions. Accuracy figures vary, with one owner reporting +9 seconds/day after demagnetization, while others find the watches to be good first "proper" watches. Some owners find the stock rubber straps uncomfortable or the overall size substantial on smaller wrists. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its combination of strong dive watch functionality and appealing design at its price point.

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