Spinnaker Dumas GMTvsSinn U18
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Owners + reviewers, side by side
Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.
Owners praise the Spinnaker Dumas GMT's satisfying lume, including on the crown, and good finishing, with one owner finding it wears well on a 17cm wrist. The watch features a Seiko NH34A GMT movement and a blue gradient dial. Reviewers note its 44mm diameter and 209g weight on the bracelet make it unsuitable for smaller wrists.
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
14 of 29 specs differFull specifications
Case
7 specsCrystal & Dial
4 specsMovement
2 specsPricing
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