Side by side

Sinn U18vsZelos Spearfish GMT

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

U18
SinnU18
MSRP $3,488
Spearfish GMT
ZelosSpearfish GMT
MSRP $999
What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

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.

Zelos Spearfish GMT

The Zelos Spearfish GMT is widely praised for its exceptional value, with reviewers highlighting its superb finishing, flawless machining, and a tool-less micro-adjustment clasp that exceeds its price point. It features a La Joux-Perret G100 movement with a 68-hour power reserve, achieving an average accuracy of +2.6 seconds per day, or a Miyota 9075 movement offering flier-style GMT functionality. The 40mm case and bidirectional 48-click ceramic bezel are well-executed, though one reviewer noted a minor compromise in the end link fit. Overall, owners and reviewers rate the Zelos Spearfish GMT highly for its impressive finishing and value proposition.

At a glance

16 of 29 specs differ
Diameter
U1844mm
Spearfish GMT40mm
Power Reserve
U1842h
Spearfish GMT40h
Water Resistance
U182,000m
Spearfish GMT200m
MSRP
U18$3,488
Spearfish GMT$999

Full specifications

Case

9 specs
Category
Diver
GMT
Diameter
44mm
40mm
Thickness
15.5mm
13mm
Lug-to-Lug
40mm
Lug Width
22mm
20mm
Material
high-strength
316L Stainless Steel
Finish
Brushed and polished
Water Resistance
2000m
200m
Caseback
Solid

Crystal & Dial

4 specs
Crystal Shape
Flat
AR Coating
Inner
Dial Color
Black
Frost
Indices
Applied

Movement

2 specs
Caliber
SW300-1
Sellita SW330-2
Power Reserve
42h
40h

Pricing

1 specs
MSRP
$3,488
$999
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