Side by side

Sinn U18vsGruppo Gamma Field III GMT

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

U18
SinnU18
MSRP $3,488
Field III GMT
Gruppo GammaField III GMT
MSRP $459
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.

Gruppo Gamma Field III GMT

Owners praise the Gruppo Gamma Field III GMT for its look and value, with specific mentions of its sandwich dial and comfortable OEM straps. One owner notes incredible quality for the price across their Gruppo Gamma watches. The watch features a 40mm brushed stainless steel case, box sapphire crystal, and a Seiko NH34A movement with a 41-hour power reserve and stated accuracy of -20~+40 s/day. Some find the lack of a date window a drawback for a GMT, and question its differentiation from other NH34-powered watches. On balance, owners and reviewers find the Gruppo Gamma Field III GMT to be a good value with quality construction for its price point.

At a glance

16 of 29 specs differ
Diameter
U1844mm
Field III GMT40mm
Power Reserve
U1842h
Field III GMT41h
Water Resistance
U182,000m
Field III GMT200m
MSRP
U18$3,488
Field III GMT$459

Full specifications

Case

8 specs
Category
Diver
GMT
Diameter
44mm
40mm
Thickness
15.5mm
14mm
Lug-to-Lug
48.5mm
Material
high-strength
Stainless Steel
Finish
Brushed and polished
Water Resistance
2000m
200m
Caseback
Solid

Crystal & Dial

4 specs
Crystal Shape
Flat
AR Coating
Yes
Indices
Applied
Lume
None
Super-LumiNova

Movement

3 specs
Caliber
SW300-1
Seiko Instruments NH38A
Power Reserve
42h
41h
Complications
None
GMT

Pricing

1 specs
MSRP
$3,488
$459
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 Sinn U18 vs Gruppo Gamma Field III GMT 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.