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 $900

At a glance

13 of 29 specs differ
Diameter
Seaforth IV40mm
Prospex Sea41mm
Power Reserve
Seaforth IV40h
Prospex Sea70h
Water Resistance
Seaforth IV200m
Prospex Sea200m
MSRP
Seaforth IV$765
Prospex Sea$900

Full specifications

Case

4 specs
Diameter
40mm
41mm
Thickness
12.4mm
12.3mm
Lug-to-Lug
46.5mm
46.9mm
Material
Titanium
Stainless Steel

Crystal & Dial

5 specs
Crystal
Sapphire (double-domed)
Sapphire
Crystal Shape
Flat
Curved
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
6R35
Power Reserve
40h
70h
Jewels
25
24

Pricing

1 specs
MSRP
$765
$900

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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

Owners widely praise the Seiko Prospex Sea for its excellent lume, robust build, and value, with many highlighting the comfortable 4 o'clock crown and reliable movements. Reviewers note impressive case finishing and attractive dials, with specific models lauded for their gradient blue designs and smooth bezel actions. Accuracy figures vary, with one owner reporting +9 seconds/day after demagnetization, while others find the watches to be good first "proper" watches. Some owners find the stock rubber straps uncomfortable or the overall size substantial on smaller wrists. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its combination of strong dive watch functionality and appealing design at its price point.

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