Side by side

Spinnaker Spence 300vsSeiko Astron

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

Spence 300
SpinnakerSpence 300
MSRP $650
Astron
SeikoAstron
MSRP $2,500

At a glance

14 of 29 specs differ
Diameter
Spence 30040mm
Astron42mm
Power Reserve
Spence 30040h
Astron40h
Water Resistance
Spence 300300m
Astron100m
MSRP
Spence 300$650
Astron$2,500

Full specifications

Case

7 specs
Category
Diver
GMT
Diameter
40mm
42mm
Thickness
11.5mm
12.4mm
Lug-to-Lug
48mm
49.5mm
Lug Width
20mm
14mm
Material
316L Stainless Steel
Titanium
Water Resistance
300m
100m

Crystal & Dial

3 specs
AR Coating
Inner
Super-clear coating
Dial Color
Aquamarine
Black
Lume
None
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
SII NH35A
5X83
Type
Automatic
Quartz
Jewels
25
14

Pricing

1 specs
MSRP
$650
$2,500

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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 Astron

Owners widely praise the Seiko Astron for its spectacular technology, solar-powered quartz movement, and GPS time synchronization, making it a convenient grab-and-go option. The watch is frequently noted for its comfortable and lightweight titanium build, with some models featuring well-finished cases and robust ceramic bezels. Reviewers and owners alike highlight the dial's dynamic and shiny appearance, with textured hour markers and high-contrast edges. Accuracy is generally considered good, with figures ranging from +/- 15 seconds per month to within 1/2 second per day, easily corrected by GPS signal. However, some owners note that DST requires manual adjustment and that automatic time syncing depends on proximity to radio wave towers. The price point is a concern for some, who feel it competes with luxury watches without the same aesthetic appeal. One owner pointed out minimal lume and a slight misalignment of the minute hand on their model.

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