Side by side

Halios Seaforth IVvsSeiko Prospex SPEEDTIMER Mechanical

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

Seaforth IV
HaliosSeaforth IV
MSRP $765
Prospex SPEEDTIMER Mechanical
SeikoProspex SPEEDTIMER Mechanical
MSRP $995

At a glance

14 of 29 specs differ
Diameter
Seaforth IV40mm
Prospex SPEEDTIMER Mechanical39.5mm
Power Reserve
Seaforth IV40h
Prospex SPEEDTIMER Mechanical72h
Water Resistance
Seaforth IV200m
Prospex SPEEDTIMER Mechanical200m
MSRP
Seaforth IV$765
Prospex SPEEDTIMER Mechanical$995

Full specifications

Case

5 specs
Category
Diver
Chronograph
Diameter
40mm
39.5mm
Thickness
12.4mm
12mm
Lug-to-Lug
46.5mm
44.5mm
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 and index(es)

Movement

3 specs
Caliber
Sellita SW200-2
6R55
Power Reserve
40h
72h
Jewels
25
24

Pricing

1 specs
MSRP
$765
$995

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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 SPEEDTIMER Mechanical

The Seiko Prospex SPEEDTIMER Mechanical is praised for its visually appealing design and comfortable wearability, with owners frequently using its chronograph function for daily tasks. Reviewers note its clean dial layout and LumiBrite treated hands and markers, and one source highlights the 72-hour power reserve of the 6R55 movement. However, some owners criticize its chronograph functionality and the 24-hour subdial. On balance, owners and reviewers rate the Seiko Prospex SPEEDTIMER Mechanical highly for its daily usability and refined aesthetics.

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