Side by side

Sinn EZM 12vsSeiko Prospex Sea 1970 Heritage Diver's Black Series Limited Edition

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

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What people say

Owners + reviewers, side by side

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

Sinn EZM 12

The Sinn EZM 12 is widely praised as a purpose-built tool watch for air rescue and medical professionals, with reviewers highlighting its innovative design for critical timing, including a one-hour countdown bezel, an internal 10-minute bezel, and a pulsometer for pulse-taking. Its Tegiment hardened case, Ar dehumidifying capsule, and easily removable components for decontamination and strap changes are consistently noted as practical strengths. Owners and reviewers also point to its value at around €2,527/$3,340 and robust magnetic resistance. However, some owners find the dial layout busy and the lume on the hands disappointing, while the winding and inner bezel crowns are reported as difficult to operate, and the 38-hour power reserve is considered less robust than expected for its serious purpose. Overall, owners and reviewers rate the Sinn EZM 12 highly for its unique, practical design and robust construction tailored for demanding professional use.

From video reviewers

The tegimented case and bezel offer superior scratch resistance. The dual rotating bezels, an inner count-up and outer countdown, allow for monitoring multiple timeframes simultaneously. Reviewers noted the pulse rotor for measuring heart rate as a unique function.

Seiko Prospex Sea 1970 Heritage Diver's Black Series Limited Edition

Owners widely praise the Seiko Prospex Sea 1970 Heritage Diver's Black Series Limited Edition for its attractive, well-made design and gorgeous dial, noting its jewel-toned teal color and rippling-water pattern. The bezel action is smooth with a muted sound, and the case and bracelet offer a more comfortable feel than previous iterations. However, multiple owners express disappointment with the accuracy of the 6R movement at its price point, with some noting theirs runs slow, and consider the price too high. The steep rehaut and marker size make the 24-hour numbers difficult to read, and some find the case design makes the watch feel top-heavy despite wearing smaller. Overall, owners rate the Seiko Prospex Sea 1970 Heritage Diver's Black Series Limited Edition highly for its striking dial and refined case design, despite concerns regarding movement accuracy at its price.

At a glance

17 of 29 specs differ
Diameter
EZM 1244mm
Prospex Sea 1970 Heritage Diver's Black Series Limited Edition44mm
Power Reserve
EZM 1238h
Prospex Sea 1970 Heritage Diver's Black Series Limited Edition50h
Water Resistance
EZM 12200m
Prospex Sea 1970 Heritage Diver's Black Series Limited Edition200m
MSRP
EZM 12$3,942
Prospex Sea 1970 Heritage Diver's Black Series Limited Edition$3,300

Full specifications

Case

6 specs
Category
Tool
Diver
Thickness
14mm
13mm
Lug-to-Lug
49.3mm
Lug Width
22mm
20mm
Finish
bead-blasted
Caseback

Crystal & Dial

5 specs
Crystal Shape
Curved
AR Coating
Underside
Anti-reflective coating on inner surface
Dial Color
Black
Indices
Lume
Luminescent
LumiBrite on hands, index(es) and bezel

Movement

5 specs
Caliber
ETA 2836-2
Seiko 8L35
Beat Rate
28,800 vph
0 vph
Power Reserve
38h
50h
Jewels
25
26
Complications
Date, Day-Date
None

Pricing

1 specs
MSRP
$3,942
$3,300
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