Side by side

Sinn 103 St Ty HdvsSeiko Prospex Sea

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

103 St Ty Hd
Sinn103 St Ty Hd
MSRP $2,797
Prospex Sea
SeikoProspex Sea
MSRP $625

At a glance

14 of 29 specs differ
Diameter
103 St Ty Hd41mm
Prospex Sea43.8mm
Power Reserve
103 St Ty Hd48h
Prospex Sea41h
Water Resistance
103 St Ty Hd200m
Prospex Sea200m
MSRP
103 St Ty Hd$2,797
Prospex Sea$625

Full specifications

Case

7 specs
Category
Tool
Diver
Diameter
41mm
43.8mm
Thickness
14.7mm
12.8mm
Lug-to-Lug
48.7mm
Lug Width
20mm
22mm
Finish
Brushed and polished
Caseback
Solid

Crystal & Dial

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

Movement

2 specs
Caliber
ETA 7750
4R35
Power Reserve
48h
41h

Pricing

1 specs
MSRP
$2,797
$625

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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 103 St Ty Hd

The Sinn 103 St Ty Hd is widely praised as a stunning, heritage-inspired pilot's chronograph with a utilitarian feel and bold red accents on a black dial. Owners note it offers a different experience compared to typical Sinn watches. It features a hand-wound Sellita SW510 M movement, a 58-hour power reserve, 20 ATM water resistance, and impact-resistant acrylic glass. The Sinn 103 St Ty Hd is priced at €2,590 and is limited to 1,000 units. On balance, owners and reviewers rate the Sinn 103 St Ty Hd highly for its unique aesthetic and tool watch attributes.

From video reviewers

The watch's robustness and ability to withstand extreme conditions without compromising accuracy are notable strengths. The relatively high price point is a shared weakness. Reviewers disagree on the watch's thickness, with one reviewer considering it a drawback and the other not mentioning it.

Seiko Prospex Sea

The Seiko Prospex Sea is widely praised for its excellent value, solid build quality, and comfortable wearability, with many models featuring impressive lume and attractive dials. Owners and reviewers highlight the modern upgrades on classic designs, such as drilled lugs and reliable movements with hacking and hand-winding capabilities. Some models are noted for their refined case finishing and scratch resistance. Accuracy figures vary, with one owner reporting approximately 4 seconds fast per day, while others find the movements offer good performance for the price. Concerns raised by owners and reviewers include clasps that can feel generic or cheap, and lug widths that some find disproportionate to the case size on certain models. The thickness and weight of some Prospex Sea watches are also noted as substantial. The GMT function on specific models is considered secondary and difficult to read for true travel purposes.

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