Side by side

CWC G40 Sonar Quartz WatchvsSeiko Prospex Sea

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
Prospex Sea
SeikoProspex Sea
MSRP $900

At a glance

12 of 29 specs differ
Diameter
G40 Sonar Quartz Watch40mm
Prospex Sea41mm
Power Reserve
G40 Sonar Quartz Watch40h
Prospex Sea70h
Water Resistance
G40 Sonar Quartz Watch200m
Prospex Sea200m
MSRP
G40 Sonar Quartz Watch$333
Prospex Sea$900

Full specifications

Case

4 specs
Category
Field
Diver
Diameter
40mm
41mm
Thickness
12mm
12.3mm
Lug-to-Lug
46mm
46.9mm

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
$900

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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.

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

Owners widely praise the Seiko Prospex Sea for its excellent lume, robust build, and value, with many highlighting the comfortable 4 o'clock crown and reliable movements. Reviewers note impressive case finishing and attractive dials, with specific models lauded for their gradient blue designs and smooth bezel actions. Accuracy figures vary, with one owner reporting +9 seconds/day after demagnetization, while others find the watches to be good first "proper" watches. Some owners find the stock rubber straps uncomfortable or the overall size substantial on smaller wrists. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its combination of strong dive watch functionality and appealing design at its price point.

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