Side by side

Bremont ionBirdvsSeiko Prospex Sea

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

ionBird
BremontionBird
MSRP $5,800
Prospex Sea
SeikoProspex Sea

At a glance

14 of 29 specs differ
Diameter
ionBird43mm
Prospex Sea42mm
Power Reserve
ionBird40h
Prospex Sea72h
Water Resistance
ionBird
Prospex Sea300m
MSRP
ionBird$5,800
Prospex Sea

Full specifications

Case

7 specs
Category
Pilot
Diver
Diameter
43mm
42mm
Thickness
13.3mm
Lug-to-Lug
48.6mm
Lug Width
20mm
Material
Titanium
Stainless Steel
Water Resistance
300m

Crystal & Dial

3 specs
AR Coating
Inner
Anti-reflective coating on inner surface
Dial Color
Regular length (15cm - 19cm wrist size)
Black
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
6R54
Power Reserve
40h
72h
Jewels
25
24

Pricing

1 specs
MSRP
$5,800

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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 ionBird

Owners report the Bremont ionBird is overpriced and features a printed dial with a poorly placed date window at 4:30, which some find visually disruptive. However, some owners suggest its case finishing is superior to competitors. The 43mm titanium Bremont ionBird GMT is powered by a COSC-certified BE-93-2AV automatic movement and retails for $5,795. On balance, owners and reviewers find the Bremont ionBird's date window placement and price point to be significant drawbacks.

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.

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