Side by side

Sinn 105 St Sa UTCvsSeiko Prospex Sea Save the Ocean Special Edition

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

105 St Sa UTC
Sinn105 St Sa UTC
MSRP $1,998

At a glance

16 of 29 specs differ
Diameter
105 St Sa UTC41mm
Prospex Sea Save the Ocean Special Edition45mm
Power Reserve
105 St Sa UTC38h
Prospex Sea Save the Ocean Special Edition41h
Water Resistance
105 St Sa UTC200m
Prospex Sea Save the Ocean Special Edition200m
MSRP
105 St Sa UTC$1,998
Prospex Sea Save the Ocean Special Edition$625

Full specifications

Case

7 specs
Category
Tool
Diver
Diameter
41mm
45mm
Thickness
11.9mm
13.2mm
Lug-to-Lug
47.7mm
Lug Width
20mm
22mm
Finish
bead-blasted
Brushed and polished
Caseback
Solid

Crystal & Dial

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

Movement

4 specs
Caliber
SW 330-2
4R36
Power Reserve
38h
41h
Jewels
25
24
Complications
Date, GMT
None

Pricing

1 specs
MSRP
$1,998
$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 105 St Sa UTC

Owners and reviewers widely praise the Sinn 105 St Sa UTC for its legible dial, precise bi-directional bezel action, and the technical, toolish aesthetic of its bead-blasted, TEGIMENT-hardened steel case. The watch is noted for its smooth sweep and snappy date change, with accuracy often within COSC standards, and its vertical day/date display with a German day wheel is a distinctive feature. Some owners find the lug-to-lug distance large for smaller wrists, and the bracelet clasp is considered a weakness by one source, while the non-lumed UTC hand is a deliberate design choice. The Sinn 105 St Sa UTC utilizes a Sellita SW330-1 automatic movement with a 42-hour power reserve and offers 200 meters of water resistance. Overall, the consensus is that owners and reviewers rate the Sinn 105 St Sa UTC highly for its robust build quality and functional tool watch design at its price point.

Seiko Prospex Sea Save the Ocean Special Edition

The Seiko Prospex Sea Save the Ocean Special Edition is widely praised for its attractive, unique, and textured dials, often described as having a "Grand Seiko feel" at a more accessible price point, with specific mentions of wave patterns, lagoon hues, and manta ray motifs. Owners appreciate the smooth bezel operation and satisfactory lume. Accuracy figures vary, with one owner reporting +5 seconds per day, while another notes a range from +1/+2 to about -6 seconds per day. The 6R35 movement offers a 70-hour power reserve, and some models feature sapphire crystals. Criticisms include a desire for exhibition casebacks and concerns about the quality and security of the stamped metal clasps and bracelets, which are frequently described as rattly or underwhelming, though this is noted as a common Seiko trait. Some owners are split on the number of Save the Ocean variations and dislike the cyclops magnifier.

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