Sangin Instruments Atlas IIIvsSeiko Prospex Sea 1965 Heritage Diver's Watch

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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.

Sangin Instruments Atlas III at true scale

Atlas III

Seiko Prospex Sea 1965 Heritage Diver's Watch at true scale

Prospex Sea 1965 Heritage Diver's Watch

Diameter

42mm

40mm

Lug-to-Lug

n/a

46.4mm

Thickness

n/a

13mm

Water Resistance

200m

300m

highest

Power Reserve

n/a

72h

MSRP

$949

lowest

$1,300

Movement

La Joux-Perret G100

Seiko 6R55

Case

6 specs
Diameter
42mm
40mm
Thickness
n/a
13mm
Lug-to-Lug
n/a
46.4mm
Lug Width
n/a
20mm
Material
n/a
Stainless Steel
Water Resistance
200m
300m

Crystal & Dial

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

Movement

3 specs
Caliber
La Joux-Perret G100
Seiko 6R55
Power Reserve
0h
72h
Jewels
0
24

Pricing

1 specs
MSRP
$949
$1,300
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Reviews

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

Sangin Instruments Atlas III

Owners widely praise the Sangin Instruments Atlas III for its great quality and value, with one owner noting it is hundreds of dollars cheaper than alternatives. The watch is reported to be in excellent condition with minor rub marks visible only up close and is keeping very good time. Some owners find the omission of minute indices bothersome, and one owner prefers a different model due to its smaller case size and lug geometry. Overall, owners rate the Sangin Instruments Atlas III highly for its excellent quality and value from a lesser-known company.

Seiko Prospex Sea 1965 Heritage Diver's Watch

Owners widely praise the Seiko Prospex Sea 1965 Heritage Diver's Watch for its refined engineering, comfortable 40mm case, and improved 300m water resistance. The watch is noted for its better build quality and finishing compared to some alternatives, featuring a mix of polished and brushed surfaces, with specific callouts for the jewel-toned teal dial with a rippling-water pattern. Some owners consider the price fair, while others suggest it is too high. Accuracy figures vary, with some owners reporting their 6R55 movement performs well within +/- 10 seconds per day, while others note theirs runs slow or have concerns about QC for the price. The bracelet, while improved, lacks modern features like quick-release or extensive micro-adjustments. Overall, owners and reviewers rate the Seiko Prospex Sea 1965 Heritage Diver's Watch highly for its refined design and build quality at its price point.