Side by side

Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special EditionvsSinn U18

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

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.

Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition

The Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition is praised for its beautiful design and refinement over previous models, featuring vertically textured glacier-inspired dials. Owners, however, consider the €1500 RRP too high, suggesting a price closer to €900-€1000, noting the aluminum bezel insert instead of ceramic. Some owners report the 6R movement runs slow. On balance, owners find the Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition beautiful and a refinement, but the price and aluminum bezel are points of contention.

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

16 of 29 specs differ
Diameter
Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition42.7mm
U1844mm
Power Reserve
Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition70h
U1842h
Water Resistance
Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition200m
U182,000m
MSRP
Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition$1,350
U18$3,488

Full specifications

Case

8 specs
Diameter
42.7mm
44mm
Thickness
13.2mm
15.5mm
Lug-to-Lug
46.4mm
Lug Width
20mm
22mm
Material
Stainless Steel
high-strength
Finish
Brushed and polished
Water Resistance
200m
2000m
Caseback
Solid

Crystal & Dial

4 specs
Crystal Shape
Curved
AR Coating
Anti-reflective coating on inner surface
Indices
Applied
Lume
LumiBrite on hands, index(es) and bezel
None

Movement

3 specs
Caliber
6R35
SW300-1
Power Reserve
70h
42h
Jewels
24
25

Pricing

1 specs
MSRP
$1,350
$3,488
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