Side by side

Bremont Supermarine 300MvsSeiko Prospex SPEEDTIMER Seiko 145th Anniversary Limited Edition

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

Supermarine 300M
BremontSupermarine 300M
MSRP $3,550

At a glance

14 of 29 specs differ
Diameter
Supermarine 300M40mm
Prospex SPEEDTIMER Seiko 145th Anniversary Limited Edition42mm
Power Reserve
Supermarine 300M40h
Prospex SPEEDTIMER Seiko 145th Anniversary Limited Edition45h
Water Resistance
Supermarine 300M300m
Prospex SPEEDTIMER Seiko 145th Anniversary Limited Edition100m
MSRP
Supermarine 300M$3,550
Prospex SPEEDTIMER Seiko 145th Anniversary Limited Edition$2,500

Full specifications

Case

6 specs
Category
Diver
Chronograph
Diameter
40mm
42mm
Thickness
12mm
14.6mm
Lug-to-Lug
49.5mm
Material
904L Stainless Steel
Stainless Steel
Water Resistance
300m
100m

Crystal & Dial

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

Movement

3 specs
Caliber
BE-92AE
8R48
Power Reserve
40h
45h
Jewels
25
34

Pricing

1 specs
MSRP
$3,550
$2,500

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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 Prospex SPEEDTIMER Seiko 145th Anniversary Limited Edition

Owners widely praise the Prospex SPEEDTIMER Seiko 145th Anniversary Limited Edition for its refined presence and intricate dial patterns, with some favoring its unique red dial and steel bezel over other Speedtimer models. However, some owners criticize the 24-hour subdial as useless, the date window as recessed, and the stock bracelet as difficult to fit, while others find the pushers stick out too much. One owner notes the $995 price point is high for the 6R55 movement, suggesting a lower range, though others appreciate the Seiko finishing and charm. On balance, owners rate the Prospex SPEEDTIMER Seiko 145th Anniversary Limited Edition well for its unique aesthetic and finishing, despite some functional and value concerns.

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