Side by side

Marathon Arctic OSAR 36mm AutomaticvsFormex Reef 39.5 mm

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
Reef 39.5 mm
FormexReef 39.5 mm
MSRP $2,230

At a glance

10 of 29 specs differ
Diameter
Arctic OSAR 36mm Automatic36mm
Reef 39.5 mm39.5mm
Power Reserve
Arctic OSAR 36mm Automatic40h
Reef 39.5 mm56h
Water Resistance
Arctic OSAR 36mm Automatic300m
Reef 39.5 mm300m
MSRP
Arctic OSAR 36mm Automatic$1,200
Reef 39.5 mm$2,230

Full specifications

Case

5 specs
Diameter
36mm
39.5mm
Thickness
13mm
11mm
Lug-to-Lug
43.5mm
45.5mm
Lug Width
18mm
22mm
Material
316L Stainless Steel
Stainless Steel

Crystal & Dial

2 specs
Dial Color
White
Bahama Blue
Lume
None
Super-LumiNova

Movement

2 specs
Caliber
Sellita SW220-1
Sellita SW300-1
Power Reserve
40h
56h

Pricing

1 specs
MSRP
$1,200
$2,230

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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.

Formex Reef 39.5 mm

The Formex Reef 39.5 mm is widely praised for its refined finishing, comfortable and well-proportioned case design, and impressive specifications for its price point, including COSC-certified Sellita SW300-1 movement and 300m water resistance. Owners and reviewers highlight the tool-less micro-adjust clasp and quick-release spring bars as practical features. Some reviewers note that the 22mm lug width feels slightly disproportionate to the smaller case, and the bracelet could benefit from more taper, though this is a point of contention for some owners who value the overall package. A prototype crown protrusion issue is noted as being addressed for production. On balance, owners and reviewers rate the Formex Reef 39.5 mm highly for its excellent value and well-executed design.

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