Side by side

Seiko Prospex SeavsFormex Reef 42 mm

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

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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.

Seiko Prospex Sea

Owners widely praise the Seiko Prospex Sea for its excellent value, solid build, and comfortable wearability, with specific mentions of its matte black dial, excellent lume, and cushion case that wears smaller than its dimensions suggest. The 4R36 movement is noted for hacking and hand-winding capabilities, and the bezel action is described as smooth and precise. Some owners find the watch to be a legitimate tool with a fair price, while others describe it as big, thick, and heavy, uncomfortable for smaller wrists, though this is subjective as one owner found the size perfect. The solar quartz movement is also highlighted as a collection-worthy feature. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its exceptional value and comfortable, classic design.

Formex Reef 42 mm

The Formex Reef 42 mm is widely praised for its comfortable bracelet featuring a micro-adjust clasp, COSC-certified Sellita movement, and excellent build quality. Owners appreciate the gradient dial's visual appeal and the overall wearability. Some owners note the seconds hand does not perfectly align with markers, and one owner found the lugs' taper hinders third-party strap fit. The bracelet's length and sporty design are noted as limiting versatility by some. On balance, owners and reviewers rate the Formex Reef 42 mm highly for its impressive wearability and value at the price point.

At a glance

10 of 29 specs differ
Diameter
Prospex Sea42mm
Reef 42 mm42mm
Power Reserve
Prospex Sea72h
Reef 42 mm56h
Water Resistance
Prospex Sea300m
Reef 42 mm300m
MSRP
Prospex Sea
Reef 42 mm$2,414

Full specifications

Case

3 specs
Thickness
13.3mm
11.4mm
Lug-to-Lug
48.6mm
47mm
Lug Width
20mm
22mm

Crystal & Dial

3 specs
AR Coating
Anti-reflective coating on inner surface
Dial Color
Black
Lume
LumiBrite on hands, index(es) and bezel
Super-LumiNova

Movement

3 specs
Caliber
Seiko 6R54
Sellita SW300-1
Power Reserve
72h
56h
Jewels
24
0

Pricing

1 specs
MSRP
$2,414
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