Side by side

Sinn 104 Classic 12vsSeiko Prospex Sea

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

What people say

Owners + reviewers, side by side

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

Sinn 104 Classic 12

The Sinn 104 Classic 12 is widely praised for its excellent legibility, comfortable wearability, and overall quality, with one owner deeming it the best watch under $3000 for their needs. Reviewers and owners alike highlight the bidirectional bezel action as a strong point, and the H-link bracelet is noted as sturdy and comfortable. However, one reviewer finds the handset and "Automatik" font slightly at odds with the dial, and another commenter describes Sinn watches as too thick with "plasticky" hands and an inner bezel edge that doesn't match promotional images. The watch is priced at €1,750, and its H-link bracelet lacks modern quick-release or micro-adjustment features. On balance, owners and reviewers rate the Sinn 104 Classic 12 highly for its pilot's tool functionality and value.

Seiko Prospex Sea

Seiko Prospex Sea models are widely praised for their excellent build quality, value for money, and comfortable wearability, with many appreciating the vintage-inspired designs and robust construction. Owners note the silicone straps are surprisingly comfortable and well-finished, and the Lumibrite lume is excellent. However, some find the 44.3mm size and thickness too large for smaller wrists, though others report the sizing as perfect. The 6R15 movement in some variants offers accuracy around +4 seconds per day with a 50-hour power reserve, while newer movements offer more. Some models are criticized for a bracelet width not matching the case size or a rudimentary clasp for their price point. Overall, owners and reviewers rate the Seiko Prospex Sea highly for its impressive case work and finishing at its price point.

At a glance

18 of 29 specs differ
Diameter
104 Classic 1241mm
Prospex Sea41.3mm
Power Reserve
104 Classic 1238h
Prospex Sea72h
Water Resistance
104 Classic 12200m
Prospex Sea300m
MSRP
104 Classic 12$2,203
Prospex Sea$1,100

Full specifications

Case

7 specs
Category
Tool
Diver
Diameter
41mm
41.3mm
Thickness
11.9mm
12.5mm
Lug-to-Lug
48.2mm
Finish
polished
Water Resistance
200m
300m
Caseback

Crystal & Dial

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

Movement

5 specs
Caliber
Sellita SW261-1
Seiko 6R55
Beat Rate
28,800 vph
0 vph
Power Reserve
38h
72h
Jewels
31
24
Complications
GMT
None

Pricing

1 specs
MSRP
$2,203
$1,100
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