Alsta NautoscaphvsSeiko 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.

Alsta Nautoscaph at true scale

Nautoscaph

Seiko Prospex Sea at true scale

Prospex Sea

Diameter

40mm

41mm

Lug-to-Lug

51.3mm

46.9mm

lowest

Thickness

16.2mm

12.3mm

lowest

Water Resistance

300m

highest

200m

Power Reserve

41h

70h

highest

MSRP

$695

lowest

$900

Movement

Seiko NH35

Seiko 6R35

Case

6 specs
Diameter
40mm
41mm
Thickness
16.2mm
12.3mm
Lug-to-Lug
51.3mm
46.9mm
Lug Width
n/a
20mm
Material
Bronze
Stainless Steel
Water Resistance
300m
200m

Crystal & Dial

4 specs
Crystal Shape
n/a
Curved
AR Coating
n/a
Anti-reflective coating on inner surface
Dial Color
n/a
n/a
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Seiko NH35
Seiko 6R35
Power Reserve
41h
70h
Jewels
0
24

Pricing

1 specs
MSRP
$695
$900
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Reviews

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

Alsta Nautoscaph

Owners widely praise the Alsta Nautoscaph for its vintage-inspired design, cinematic appearances in films like "Jaws" and "Fear and Loathing in Las Vegas," and its "70s cool" aesthetic. Reviewers note its contrasting case finishes and functional, lumed dial, though the absence of a lumed numeral at 3 o'clock due to the date window is a minor drawback. One reviewer flags the watch's 15.1mm thickness and poor bracelet execution as significant issues, deeming it a "colossal failure" at its price point, while another owner suggests it is egregiously overpriced at MSRP but a fun summer piece in the $500-600 range. On balance, owners and reviewers are divided on the Alsta Nautoscaph's value and wearability, with its aesthetic appeal and cinematic provenance being its strongest selling points.

Seiko Prospex Sea

Owners widely praise the Seiko Prospex Sea for its value and robust build, with many highlighting its excellent lume and attractive design. Some owners find the 41mm case size perfect, while others with smaller wrists consider it too large, thick, and heavy. The stock rubber strap is noted as uncomfortable for land wear by one owner. Overall, owners rate the Seiko Prospex Sea highly for its design and value at the price point.