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
MSRP $900

At a glance

15 of 29 specs differ
Diameter
ionBird43mm
Prospex Sea41mm
Power Reserve
ionBird40h
Prospex Sea70h
Water Resistance
ionBird
Prospex Sea200m
MSRP
ionBird$5,800
Prospex Sea$900

Full specifications

Case

7 specs
Category
Pilot
Diver
Diameter
43mm
41mm
Thickness
12.3mm
Lug-to-Lug
46.9mm
Lug Width
20mm
Material
Titanium
Stainless Steel
Water Resistance
200m

Crystal & Dial

4 specs
Crystal Shape
Flat
Curved
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
6R35
Power Reserve
40h
70h
Jewels
25
24

Pricing

1 specs
MSRP
$5,800
$900

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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 lume, robust build, and value, with many highlighting the comfortable 4 o'clock crown and reliable movements. Reviewers note impressive case finishing and attractive dials, with specific models lauded for their gradient blue designs and smooth bezel actions. Accuracy figures vary, with one owner reporting +9 seconds/day after demagnetization, while others find the watches to be good first "proper" watches. Some owners find the stock rubber straps uncomfortable or the overall size substantial on smaller wrists. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its combination of strong dive watch functionality and appealing design at its price point.

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