Side by side

Marathon Steel Navigator SSNAV AutovsSinn U18

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
U18
SinnU18
MSRP $3,488
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.

Sinn U18

The Sinn U18 is praised for its unique deep blue/green dial with three-dimensional oxygen bubbles that change with light, and its comfortable, easily adjustable bracelet. Owners find the watch stunning and a piece of history, appreciating the refined hands. The Sinn U18 features a 44mm, 15.5mm thick case made from German submarine steel, offering a 2000-meter dive specification and Sinn's Ar-Dehumidifying technology, powered by a Sellita SW300-1 movement. The case thickness is apparent, and the watch comes as a complete set with box and papers for $3,000-$3,680. On balance, owners and reviewers rate the Sinn U18 highly for its striking dial and robust build.

At a glance

15 of 29 specs differ
Diameter
Steel Navigator SSNAV Auto41mm
U1844mm
Power Reserve
Steel Navigator SSNAV Auto40h
U1842h
Water Resistance
Steel Navigator SSNAV Auto60m
U182,000m
MSRP
Steel Navigator SSNAV Auto$1,300
U18$3,488

Full specifications

Case

9 specs
Category
Pilot
Diver
Diameter
41mm
44mm
Thickness
11.5mm
15.5mm
Lug-to-Lug
48mm
Lug Width
20mm
22mm
Material
316L Stainless Steel
high-strength
Finish
Brushed and polished
Water Resistance
60m
2000m
Caseback
Solid

Crystal & Dial

3 specs
Crystal Shape
Flat
AR Coating
Inner
Indices
Applied

Movement

2 specs
Caliber
Sellita SW200-1
SW300-1
Power Reserve
40h
42h

Pricing

1 specs
MSRP
$1,300
$3,488
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.

Follow this matchup

Get a note when Marathon Steel Navigator SSNAV Auto vs Sinn U18 gets more votes, a community discussion, or a price drop. No account needed.

Adjacent matchups

People also compared

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