Side by side

Spinnaker Spence 300vsSeiko Prospex Sea

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

Spence 300
SpinnakerSpence 300
MSRP $650
Prospex Sea
SeikoProspex Sea
MSRP $595

At a glance

12 of 29 specs differ
Diameter
Spence 30040mm
Prospex Sea41.7mm
Power Reserve
Spence 30040h
Prospex Sea41h
Water Resistance
Spence 300300m
Prospex Sea200m
MSRP
Spence 300$650
Prospex Sea$595

Full specifications

Case

5 specs
Diameter
40mm
41.7mm
Thickness
11.5mm
12.3mm
Lug-to-Lug
48mm
49.5mm
Material
316L Stainless Steel
Stainless Steel
Water Resistance
300m
200m

Crystal & Dial

3 specs
Crystal
Sapphire
Hardlex
Dial Color
Aquamarine
Black
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
SII NH35A
4R35
Power Reserve
40h
41h
Jewels
25
23

Pricing

1 specs
MSRP
$650
$595

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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.

Spinnaker Spence 300

The Spinnaker Spence 300 is widely praised for its slim 10.9mm case and 40mm diameter, offering a comfortable and uncommon thin diver design at its price point. Reviewers and owners highlight its value, especially below $350, and its blend of retro design with modern specifications, including a 300m depth rating and a fully indexed bezel. Some owners, however, find the dial printing and bracelet finishing to be less refined, with one noting the bracelet's male end links as a drawback. The consensus is that the Spinnaker Spence 300 is highly regarded for its exceptional value and wearable dimensions, making it a strong contender for an everyday sports watch.

Seiko Prospex Sea

Owners and reviewers widely praise the Seiko Prospex Sea for its excellent value, robust build, and superior lume, with many noting its comfortable wearability and faithful design recreations. Some owners report the watch can feel big, thick, and heavy on smaller wrists, while others find the sizing perfect. The bezel action is frequently highlighted as smooth and precise, often exceeding that of less expensive models. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its impressive finishing and value proposition.

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