Side by side

CWC G40 Sonar Quartz WatchvsSeiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition

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

G40 Sonar Quartz Watch
CWCG40 Sonar Quartz Watch
MSRP $333
What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

CWC G40 Sonar Quartz Watch

Owners widely appreciate the CWC G40 Sonar Quartz Watch for its classic G10 design, 40mm case size, and 20atm water resistance, noting its light, rugged, and reliable "grab-n-go" nature. Some find the dial proportions have too much negative space, while others praise its unique anodized red crown and quality NATO straps. A larger crown can dig into the wrist, and the lack of a battery hatch is a trade-off for its 100m water resistance. On balance, owners value the CWC G40 Sonar Quartz Watch for its robust build and classic aesthetic, though its price point and competition are frequently cited concerns.

Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition

The Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition is praised for its beautiful design and refinement over previous models, featuring vertically textured glacier-inspired dials. Owners, however, consider the €1500 RRP too high, suggesting a price closer to €900-€1000, noting the aluminum bezel insert instead of ceramic. Some owners report the 6R movement runs slow. On balance, owners find the Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition beautiful and a refinement, but the price and aluminum bezel are points of contention.

At a glance

12 of 29 specs differ
Diameter
G40 Sonar Quartz Watch40mm
Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition42.7mm
Power Reserve
G40 Sonar Quartz Watch40h
Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition70h
Water Resistance
G40 Sonar Quartz Watch200m
Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition200m
MSRP
G40 Sonar Quartz Watch$333
Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition$1,350

Full specifications

Case

4 specs
Category
Field
Diver
Diameter
40mm
42.7mm
Thickness
12mm
13.2mm
Lug-to-Lug
46mm
46.4mm

Crystal & Dial

4 specs
Crystal Shape
Flat
Curved
AR Coating
Yes
Anti-reflective coating on inner surface
Dial Color
CWC G40 Sonar Quartz Watch
Black
Lume
Super-LumiNova
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
6R35
Power Reserve
40h
70h
Jewels
25
24

Pricing

1 specs
MSRP
$333
$1,350
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