Side by side

Tudor Black BayvsSinn U18

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

Black Bay
TudorBlack Bay
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.

Tudor Black Bay

Owners widely praise the Tudor Black Bay for its comfortable wearability, robust build, and vintage-inspired aesthetics, with specific mentions of its satisfying winding feel and sturdy bezel action. Reviewers highlight the 39mm Black Bay 58's comfortable size and thinness, while others note the 41mm Master Chronometer's reliable timekeeping and magnetic resistance. Some owners find the GMT hand difficult to distinguish in low light. A recurring point of contention across multiple sources is the lack of on-the-fly micro-adjustment on the bracelet, though some find aftermarket solutions adequate. One owner reported the watch losing two minutes a day after six years, requiring a service. Overall, owners and reviewers rate the Tudor Black Bay highly for its blend of vintage charm, modern robustness, and comfortable wearability.

From video reviewers

The COSC-certified accuracy of the movement is a notable strength. The 14.7mm to 14.8mm thickness is cited as a potential drawback. Reviewers are divided on whether the newer models represent a departure from the Black Bay's heritage design.

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

13 of 29 specs differ
Diameter
Black Bay41mm
U1844mm
Power Reserve
Black Bay70h
U1842h
Water Resistance
Black Bay200m
U182,000m
MSRP
Black Bay
U18$3,488

Full specifications

Case

7 specs
Diameter
41mm
44mm
Thickness
14.7mm
15.5mm
Lug-to-Lug
46mm
Material
Stainless Steel
high-strength
Finish
Polished + Satin
Water Resistance
200m
2000m
Caseback
Engraved

Crystal & Dial

3 specs
Crystal Shape
Flat
AR Coating
Inner
Indices
Applied

Movement

2 specs
Caliber
MT5602
Sellita SW300-1
Power Reserve
70h
42h

Pricing

1 specs
MSRP
$3,488
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