Side by side

Seiko Prospex SeavsSeiko 5KX

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

What people say

Owners + reviewers, side by side

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

Seiko Prospex Sea

Seiko Prospex Sea models are widely praised for their excellent build quality, value for money, and comfortable wearability, with many appreciating the vintage-inspired designs and robust construction. Owners note the silicone straps are surprisingly comfortable and well-finished, and the Lumibrite lume is excellent. However, some find the 44.3mm size and thickness too large for smaller wrists, though others report the sizing as perfect. The 6R15 movement in some variants offers accuracy around +4 seconds per day with a 50-hour power reserve, while newer movements offer more. Some models are criticized for a bracelet width not matching the case size or a rudimentary clasp for their price point. Overall, owners and reviewers rate the Seiko Prospex Sea highly for its impressive case work and finishing at its price point.

Seiko 5KX

Owners widely praise the Seiko 5 Sports SKX series for its strong lume and comfortable wearability, with many noting its compact feel due to a short lug-to-lug length. The NH36 movement's accuracy varies, with typical performance between +/-5 to 10 seconds per day, though some report better. A lack of screw-down crown and ISO certification are noted drawbacks for its water resistance. Some owners find the bracelet to be of cheaper construction with hollow links, and a few have reported quality control issues. The consensus is that the Seiko 5 Sports SKX series offers good value for its price, appealing to those who appreciate its tool-like nature and iconic lineage.

At a glance

11 of 29 specs differ
Diameter
Prospex Sea41.3mm
5KX42.5mm
Power Reserve
Prospex Sea72h
5KX41h
Water Resistance
Prospex Sea300m
5KX100m
MSRP
Prospex Sea$1,100
5KX$350

Full specifications

Case

5 specs
Diameter
41.3mm
42.5mm
Thickness
12.5mm
13.4mm
Lug-to-Lug
48.2mm
46mm
Lug Width
20mm
22mm
Water Resistance
300m
100m

Crystal & Dial

3 specs
Crystal
Sapphire
Hardlex
AR Coating
Anti-reflective coating on inner surface
Lume
LumiBrite on hands, index(es) and bezel
LumiBrite on hands and index(es)

Movement

2 specs
Caliber
6R55
Seiko 4R36
Power Reserve
72h
41h

Pricing

1 specs
MSRP
$1,100
$350
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