Side by side

Halios Seaforth IVvsSeestern S450 Ocean Star

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

Seaforth IV
HaliosSeaforth IV
MSRP $765
S450 Ocean Star
SeesternS450 Ocean Star
MSRP $299

At a glance

13 of 29 specs differ
Diameter
Seaforth IV40mm
S450 Ocean Star40mm
Power Reserve
Seaforth IV40h
S450 Ocean Star41h
Water Resistance
Seaforth IV200m
S450 Ocean Star100m
MSRP
Seaforth IV$765
S450 Ocean Star$299

Full specifications

Case

4 specs
Thickness
12.4mm
12mm
Lug-to-Lug
46.5mm
48mm
Material
Titanium
316L Stainless Steel
Water Resistance
200m
100m

Crystal & Dial

3 specs
Crystal
Sapphire (double-domed)
Sapphire
Dial Color
Blue
White
Lume
None
Tritium

Movement

5 specs
Caliber
Sellita SW200-2
TMI NH35A
Beat Rate
28,800 vph
21,600 vph
Power Reserve
40h
41h
Jewels
25
24
Complications
None
GMT, Date

Pricing

1 specs
MSRP
$765
$299

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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.

Halios Seaforth IV

Owners widely praise the Halios Sunburst Blue for its perfect 40mm size, stunning sunburst dial, and excellent lume, with one owner calling it Halios's best effort and a potential "Omega AT killer." The ETA 2824 movement is noted as running smoothly, and the watch is considered a great value with strong resale. Some owners desire larger sizes or different dial colors, and one reviewer found the Sinn 556i more versatile. The sapphire bezel is described as tall and flat, which is a point of contention for some. Overall, owners rate the Halios Sunburst Blue highly for its design, size, and value.

From video reviewers

The sunburst blue dial is a standout feature. Limited water resistance is a shared concern.

Seestern S450 Ocean Star

Owners widely praise the Seestern S450 Ocean Star's Yachtmaster-style case and flawless bracelet finishing, with one owner noting the ST2130 movement keeps good time. The bezel action is described as having individual notches but feeling like a friction bezel, while another owner flags the bezel and crown action as smooth with perfect alignment. Lume is a point of contention, with one source describing it as a nice cool blue with ice-white application, while others note it as weak or not matching Prospex standards, despite using BGW-9. The watch is considered a "big boy" ideal for larger wrists (19cm+), potentially too large for 17cm wrists due to its size and non-tapering bracelet. Overall, owners rate the Seestern S450 Ocean Star highly for its build quality and finishing at the price point, despite some reservations about its size and lume intensity.

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