Side by side

Borealis Watch Co. SintravsSeiko Prospex Sea

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

Sintra
Borealis Watch Co.Sintra
MSRP $650
Prospex Sea
SeikoProspex Sea
MSRP $625

At a glance

11 of 29 specs differ
Diameter
Sintra41.50mm
Prospex Sea43.8mm
Power Reserve
Sintra40h
Prospex Sea41h
Water Resistance
Sintra200m
Prospex Sea200m
MSRP
Sintra$650
Prospex Sea$625

Full specifications

Case

5 specs
Category
Sport
Diver
Diameter
41.50mm
43.8mm
Thickness
12.95mm
12.8mm
Lug-to-Lug
47.00mm
48.7mm
Lug Width
20mm
22mm

Crystal & Dial

2 specs
AR Coating
Inner
Anti-reflective coating on inner surface
Lume
BGW9
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Miyota 9015
4R35
Power Reserve
40h
41h
Jewels
25
23

Pricing

1 specs
MSRP
$650
$625

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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.

Borealis Watch Co. Sintra

Borealis Watch Co. Sintra owners widely praise its well-executed design, featuring applied indices and a shimmering blue dial that some prefer over more expensive alternatives. The timepiece is noted for excellent build quality and high-end specifications for its price, including a Miyota 90S5 movement and a premium bracelet. One owner did not purchase due to its size not being 39mm or less, while the 90xx movements are considered reliable and accurate, though some find them noisy. On balance, owners rate the Borealis Watch Co. Sintra highly for its impressive design and build quality at its price point.

Seiko Prospex Sea

The Seiko Prospex Sea is widely praised for its excellent value, solid build quality, and comfortable wearability, with many models featuring impressive lume and attractive dials. Owners and reviewers highlight the modern upgrades on classic designs, such as drilled lugs and reliable movements with hacking and hand-winding capabilities. Some models are noted for their refined case finishing and scratch resistance. Accuracy figures vary, with one owner reporting approximately 4 seconds fast per day, while others find the movements offer good performance for the price. Concerns raised by owners and reviewers include clasps that can feel generic or cheap, and lug widths that some find disproportionate to the case size on certain models. The thickness and weight of some Prospex Sea watches are also noted as substantial. The GMT function on specific models is considered secondary and difficult to read for true travel purposes.

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