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 $1,100

At a glance

12 of 29 specs differ
Diameter
Sintra41.50mm
Prospex Sea41.3mm
Power Reserve
Sintra40h
Prospex Sea72h
Water Resistance
Sintra200m
Prospex Sea300m
MSRP
Sintra$650
Prospex Sea$1,100

Full specifications

Case

6 specs
Category
Sport
Diver
Diameter
41.50mm
41.3mm
Thickness
12.95mm
12.5mm
Lug-to-Lug
47.00mm
48.2mm
Lug Width
20mm
20mm
Water Resistance
200m
300m

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
6R55
Power Reserve
40h
72h
Jewels
25
24

Pricing

1 specs
MSRP
$650
$1,100

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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

Seiko Prospex Sea models are widely praised for their excellent build quality, value for money, and comfortable wearability, with many appreciating the vintage-inspired designs and robust construction. Owners note the silicone straps are surprisingly comfortable and well-finished, and the Lumibrite lume is excellent. However, some find the 44.3mm size and thickness too large for smaller wrists, though others report the sizing as perfect. The 6R15 movement in some variants offers accuracy around +4 seconds per day with a 50-hour power reserve, while newer movements offer more. Some models are criticized for a bracelet width not matching the case size or a rudimentary clasp for their price point. Overall, owners and reviewers rate the Seiko Prospex Sea highly for its impressive case work and finishing at its price point.

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