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 $625

At a glance

13 of 29 specs differ
Diameter
Spence 30040mm
Prospex Sea43.8mm
Power Reserve
Spence 30040h
Prospex Sea41h
Water Resistance
Spence 300300m
Prospex Sea200m
MSRP
Spence 300$650
Prospex Sea$625

Full specifications

Case

6 specs
Diameter
40mm
43.8mm
Thickness
11.5mm
12.8mm
Lug-to-Lug
48mm
48.7mm
Lug Width
20mm
22mm
Material
316L Stainless Steel
Stainless Steel
Water Resistance
300m
200m

Crystal & Dial

3 specs
AR Coating
Inner
Anti-reflective coating on inner surface
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
$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.

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

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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