Side by side

Halios Seaforth IVvsSeiko Prospex Sea

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

Seaforth IV
HaliosSeaforth IV
MSRP $765
Prospex Sea
SeikoProspex Sea
MSRP $625

At a glance

13 of 29 specs differ
Diameter
Seaforth IV40mm
Prospex Sea43.8mm
Power Reserve
Seaforth IV40h
Prospex Sea41h
Water Resistance
Seaforth IV200m
Prospex Sea200m
MSRP
Seaforth IV$765
Prospex Sea$625

Full specifications

Case

5 specs
Diameter
40mm
43.8mm
Thickness
12.4mm
12.8mm
Lug-to-Lug
46.5mm
48.7mm
Lug Width
20mm
22mm
Material
Titanium
Stainless Steel

Crystal & Dial

4 specs
Crystal
Sapphire (double-domed)
Sapphire
AR Coating
Inner
Anti-reflective coating on inner surface
Dial Color
Blue
Black
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Sellita SW200-2
4R35
Power Reserve
40h
41h
Jewels
25
23

Pricing

1 specs
MSRP
$765
$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.

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.

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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