Side by side

Islander Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300vsGrand Seiko SLGA015

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

Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300
IslanderIslander Greenport 39mm Dive Watch with Black and White Dial #ISL-300
MSRP $399
SLGA015
Grand SeikoSLGA015
MSRP $12,600

At a glance

17 of 29 specs differ
Diameter
Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-30039mm
SLGA01543.8mm
Power Reserve
Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300
SLGA015120h
Water Resistance
Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300200m
SLGA015200m
MSRP
Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300$399
SLGA015$12,600

Full specifications

Case

7 specs
Diameter
39mm
43.8mm
Thickness
13mm
13.8mm
Lug-to-Lug
0mm
51.5mm
Lug Width
20mm
23mm
Material
Stainless Steel
Titanium
Finish
Brushed and polished
Caseback
Screw-down
Solid

Crystal & Dial

4 specs
Crystal Shape
Flat
AR Coating
Underside
Yes
Dial Color
Black
Indices
Applied

Movement

5 specs
Caliber
Miyota 8205
9RA5
Type
Automatic
Spring Drive
Beat Rate
0 vph
28,800 vph
Power Reserve
0h
120h
Jewels
0
25

Pricing

1 specs
MSRP
$399
$12,600

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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.

Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300

The Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300 is praised for its 39mm size and comfortable fit, with its bi-directional dual time bezel noted as a useful feature for tracking different time zones. Owners appreciate the lumed ceramic bezel and the slightly domed sapphire crystal. One owner specifically highlights the dial layout as a strong positive. The screw-down crown is also mentioned as a nice touch. On balance, owners rate the Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300 highly for its wearability and functional bezel.

Grand Seiko SLGA015

The Grand Seiko SLGA015 is widely praised for its exceptional accuracy, with owners reporting performance far exceeding the stated 10 seconds per month. The Spring Drive movement's smooth sweep and 5-day power reserve are also noted strengths, as is the lighter titanium case construction. However, some owners find the bracelet extension non-intuitive, and one noted the clasp scratched easily. The watch features a nature-inspired, wave-like dial texture. Overall, owners rate the Grand Seiko SLGA015 highly for its impressive accuracy and quality construction.

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