Side by side

Spinnaker Bradner GMTvsSeiko Astron

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

Bradner GMT
SpinnakerBradner GMT
MSRP $299
Astron
SeikoAstron
MSRP $2,500

At a glance

12 of 29 specs differ
Diameter
Bradner GMT42mm
Astron42mm
Power Reserve
Bradner GMT40h
Astron40h
Water Resistance
Bradner GMT180m
Astron100m
MSRP
Bradner GMT$299
Astron$2,500

Full specifications

Case

5 specs
Thickness
15mm
12.4mm
Lug-to-Lug
50mm
49.5mm
Lug Width
22mm
14mm
Material
316L Stainless Steel
Titanium
Water Resistance
180m
100m

Crystal & Dial

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

Movement

3 specs
Caliber
Seiko NH34A
5X83
Type
Automatic
Quartz
Jewels
25
14

Pricing

1 specs
MSRP
$299
$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 Bradner GMT

The Spinnaker Bradner GMT is praised for its awesome lume and comfortable wearability, with one owner noting the rubber strap is very comfortable and the beads of rice bracelet fits well on smaller wrists. Some find its 15mm thickness and bold colorway may not appeal to everyone, and one owner views it as more of a casual GMT with tool-watch styling than a diver. Overall, owners rate the Spinnaker Bradner GMT highly for its value and comfortable wearability.

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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