Seiko Baby AlpinistvsSeiko Prospex Sea

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Measurements

Catalog photos are all shot at the same flattering size. These aren't: every case below shares one millimeter scale.

Seiko Baby Alpinist at true scale

Baby Alpinist

Seiko Prospex Sea at true scale

Prospex Sea

Diameter

38mm

41.7mm

Lug-to-Lug

46mm

lowest

49.5mm

Thickness

12.9mm

12.3mm

lowest

Water Resistance

200m

200m

Power Reserve

70h

highest

41h

MSRP

$725

$595

lowest

Movement

Seiko 6R35

Seiko 4R35

Case

4 specs
Category
Field
Diver
Diameter
38mm
41.7mm
Thickness
12.9mm
12.3mm
Lug-to-Lug
46mm
49.5mm

Crystal & Dial

4 specs
Crystal
Sapphire
Hardlex
Crystal Shape
Curved
n/a
AR Coating
Anti-reflective coating on inner surface
n/a
Lume
LumiBrite on hands and index(es)
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Seiko 6R35
Seiko 4R35
Power Reserve
70h
41h
Jewels
24
23

Pricing

1 specs
MSRP
$725
$595
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Reviews

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

Seiko Baby Alpinist

Owners widely praise the Seiko Baby Alpinist for its attractive design, legible dial, and comfortable 38mm cushion case that wears smaller than its dimensions suggest. Reviewers and owners alike highlight the watch's excellent value, particularly when on sale, and appreciate its finishing, including outstanding brushing and a gorgeous reflective dial with applied indices. Some reviewers note the internal rotating bezel action is good for the price, though not as refined as higher-end models, and one owner would prefer a numbered bezel. A drawback mentioned by one owner is the lack of AR coating, and accuracy is reported by one source as approximately -10 seconds per day. The stock strap is frequently described as stiff and uncomfortable, though owners find success with break-in or replacement. Overall, owners and reviewers rate the Seiko Baby Alpinist highly for its comfortable wearability and attractive finishing at a fair price.

From video reviewers

The watch's bezel action is smooth and precise. The watch's lume is somewhat lacking, with the hour markers not being as bright as they'd like. Reviewers disagree on the ideal case size, with some preferring 38mm and others 41.4mm.

Seiko Prospex Sea

Owners widely report the Seiko Prospex Sea is a well-built watch at a fair price, with some finding its 41.7mm case size perfect while others with smaller wrists consider it big, thick, and heavy. Reviewers consistently praise the excellent lume and robust design. One owner notes the bezel action is smoother and more precise than some other Seiko divers. Overall, owners and reviewers rate the Seiko Prospex Sea highly for its value and proven design.