Side by side

Seiko Prospex SeavsSeestern S456 GMT

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

Prospex Sea
SeikoProspex Sea
S456 GMT
SeesternS456 GMT
MSRP $299

At a glance

15 of 29 specs differ
Diameter
Prospex Sea42mm
S456 GMT41mm
Power Reserve
Prospex Sea72h
S456 GMT41hh
Water Resistance
Prospex Sea300m
S456 GMT200m
MSRP
Prospex Sea
S456 GMT$299

Full specifications

Case

7 specs
Category
Diver
GMT
Diameter
42mm
41mm
Thickness
13.3mm
13mm
Lug-to-Lug
48.6mm
49mm
Material
Stainless Steel
316L Stainless Steel
Finish
Brushed and polished
Brushed + Polished
Water Resistance
300m
200m

Crystal & Dial

3 specs
AR Coating
Anti-reflective coating on inner surface
Inner
Dial Color
Black
Sunray style, applied and Diamond cut Indices, C1 lume
Lume
LumiBrite on hands, index(es) and bezel
C1

Movement

4 specs
Caliber
6R54
Seiko NH34
Beat Rate
28,800 vph
3 vph
Power Reserve
72h
41hh
Complications
None
GMT

Pricing

1 specs
MSRP
$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.

Seiko Prospex Sea

Owners widely praise the Seiko Prospex Sea for its excellent value, solid build, and comfortable wearability, with specific mentions of its matte black dial, excellent lume, and cushion case that wears smaller than its dimensions suggest. The 4R36 movement is noted for hacking and hand-winding capabilities, and the bezel action is described as smooth and precise. Some owners find the watch to be a legitimate tool with a fair price, while others describe it as big, thick, and heavy, uncomfortable for smaller wrists, though this is subjective as one owner found the size perfect. The solar quartz movement is also highlighted as a collection-worthy feature. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its exceptional value and comfortable, classic design.

Seestern S456 GMT

Owners widely praise the Seestern S456 GMT for its exceptional value and finishing that exceeds expectations, with one owner noting its accuracy surpasses that of their Seiko 5. The dial displays a pearl-like rainbow effect. Some owners would prefer a bidirectional bezel over the current unidirectional one. The Seestern S456 GMT features an NH34 movement, a 39.5mm case, sapphire crystal, and an adjustable clasp. On balance, owners rate the Seestern S456 GMT highly for its impressive finishing and value proposition at its price point.

From video reviewers

The watch features stunning, detailed finishing that is difficult to top. Reviewers did not reach a consensus on any weaknesses.

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