Side by side

Formex Reef 42 mmvsSeiko Prospex Sea

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

Reef 42 mm
FormexReef 42 mm
MSRP $2,414
Prospex Sea
SeikoProspex Sea
MSRP $595

At a glance

11 of 29 specs differ
Diameter
Reef 42 mm42mm
Prospex Sea41.7mm
Power Reserve
Reef 42 mm56h
Prospex Sea41h
Water Resistance
Reef 42 mm300m
Prospex Sea200m
MSRP
Reef 42 mm$2,414
Prospex Sea$595

Full specifications

Case

5 specs
Diameter
42mm
41.7mm
Thickness
11.4mm
12.3mm
Lug-to-Lug
47mm
49.5mm
Lug Width
22mm
20mm
Water Resistance
300m
200m

Crystal & Dial

2 specs
Crystal
Sapphire
Hardlex
Lume
Super-LumiNova
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Sellita SW300-1
4R35
Power Reserve
56h
41h
Jewels
25
23

Pricing

1 specs
MSRP
$2,414
$595

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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.

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.

Seiko Prospex Sea

Owners and reviewers widely praise the Seiko Prospex Sea for its excellent value, robust build, and superior lume, with many noting its comfortable wearability and faithful design recreations. Some owners report the watch can feel big, thick, and heavy on smaller wrists, while others find the sizing perfect. The bezel action is frequently highlighted as smooth and precise, often exceeding that of less expensive models. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its impressive finishing and value proposition.

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