Side by side

Bremont Supermarine 300MvsSeiko Monster

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

Supermarine 300M
BremontSupermarine 300M
MSRP $3,550
Monster
SeikoMonster
MSRP $550

At a glance

12 of 29 specs differ
Diameter
Supermarine 300M40mm
Monster42.4mm
Power Reserve
Supermarine 300M40h
Monster41h
Water Resistance
Supermarine 300M300m
Monster200m
MSRP
Supermarine 300M$3,550
Monster$550

Full specifications

Case

5 specs
Diameter
40mm
42.4mm
Thickness
12mm
13.4mm
Lug-to-Lug
49.4mm
Material
904L Stainless Steel
Stainless Steel
Water Resistance
300m
200m

Crystal & Dial

3 specs
Crystal
Sapphire
Hardlex
Dial Color
Green
Black
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
BE-92AE
4R36
Power Reserve
40h
41h
Jewels
25
24

Pricing

1 specs
MSRP
$3,550
$550

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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.

Bremont Supermarine 300M

The Bremont Supermarine 300M is praised for its comfortable 40mm and 42mm case sizes, with owners noting the 42mm wears well on smaller wrists due to its lug design. One owner highlights the 13mm thinness of the 40mm case, considered compact for a 300m diver. The watch is priced at $1375. On balance, owners and reviewers appreciate the Bremont Supermarine 300M for its wearability and compact dimensions, especially for a dive watch.

Seiko Monster

Owners widely praise the Seiko Prospex Sea for its excellent value, robust build, and superb lume, with many noting its comfortable wearability. Reviewers consistently highlight its impressive finishing and classic dive watch design, often comparing it favorably to older models. Some owners find the size substantial, with one noting it as big, thick, and heavy on a 6.5-inch wrist, while others find it perfect. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its exceptional value and robust, classic dive watch design.

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