Side by side

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

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
Prospex Sea
SeikoProspex Sea
MSRP $625

At a glance

16 of 29 specs differ
Diameter
Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-30039mm
Prospex Sea43.8mm
Power Reserve
Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300
Prospex Sea41h
Water Resistance
Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300200m
Prospex Sea200m
MSRP
Islander Greenport 39mm Dive Watch with Black and White Dial #ISL-300$399
Prospex Sea$625

Full specifications

Case

6 specs
Diameter
39mm
43.8mm
Thickness
13mm
12.8mm
Lug-to-Lug
0mm
48.7mm
Lug Width
20mm
22mm
Finish
Brushed and polished
Caseback
Screw-down
Solid

Crystal & Dial

5 specs
Crystal Shape
Flat
AR Coating
Underside
Anti-reflective coating on inner surface
Dial Color
Black
Indices
Applied
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

4 specs
Caliber
Miyota 8205
4R35
Beat Rate
0 vph
28,800 vph
Power Reserve
0h
41h
Jewels
0
23

Pricing

1 specs
MSRP
$399
$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.

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.

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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