Side by side

Marathon Arctic OSAR 36mm AutomaticvsSeiko Prospex Sea

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

Arctic OSAR 36mm Automatic
MarathonArctic OSAR 36mm Automatic
MSRP $1,200
Prospex Sea
SeikoProspex Sea
MSRP $900

At a glance

14 of 29 specs differ
Diameter
Arctic OSAR 36mm Automatic36mm
Prospex Sea41mm
Power Reserve
Arctic OSAR 36mm Automatic40h
Prospex Sea70h
Water Resistance
Arctic OSAR 36mm Automatic300m
Prospex Sea200m
MSRP
Arctic OSAR 36mm Automatic$1,200
Prospex Sea$900

Full specifications

Case

6 specs
Diameter
36mm
41mm
Thickness
13mm
12.3mm
Lug-to-Lug
43.5mm
46.9mm
Lug Width
18mm
20mm
Material
316L Stainless Steel
Stainless Steel
Water Resistance
300m
200m

Crystal & Dial

4 specs
Crystal Shape
Flat
Curved
AR Coating
Inner
Anti-reflective coating on inner surface
Dial Color
White
Black
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Sellita SW220-1
6R35
Power Reserve
40h
70h
Jewels
25
24

Pricing

1 specs
MSRP
$1,200
$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.

Marathon Arctic OSAR 36mm Automatic

The Marathon Arctic OSAR 36mm Automatic is noted for its non-tritium dial option, though some owners prefer the 1-12 numeral layout found on other models. One owner found the 36mm size too small for their wrist. Overall, owners appreciate the Marathon Arctic OSAR 36mm Automatic for its non-tritium dial option.

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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