Side by side

Borealis Watch Co. Porto CovovsSeestern S450 Ocean Star

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

Porto Covo
Borealis Watch Co.Porto Covo
MSRP $415
S450 Ocean Star
SeesternS450 Ocean Star
MSRP $299

At a glance

14 of 29 specs differ
Diameter
Porto Covo40mm
S450 Ocean Star40mm
Power Reserve
Porto Covo40h
S450 Ocean Star41h
Water Resistance
Porto Covo300m
S450 Ocean Star100m
MSRP
Porto Covo$415
S450 Ocean Star$299

Full specifications

Case

6 specs
Diameter
40mm
40mm
Thickness
11.6mm
12mm
Lug-to-Lug
42.5mm
48mm
Lug Width
20mm
20mm
Material
Stainless Steel
316L Stainless Steel
Water Resistance
300m
100m

Crystal & Dial

2 specs
Dial Color
Black
White
Lume
BGW9
Tritium

Movement

5 specs
Caliber
Miyota 9039
TMI NH35A
Beat Rate
28,800 vph
21,600 vph
Power Reserve
40h
41h
Jewels
25
24
Complications
None
GMT, Date

Pricing

1 specs
MSRP
$415
$299

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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. Porto Covo

The Borealis Porto Covo is widely praised for its 39mm size and unique cantilevered indices that create a 3D effect and depth. Owners note the indices' floating appearance is a well-executed design. One owner reported poor accuracy and a terse customer service response, while another wished for a 42mm size option. The $395 price is considered reasonable for a microbrand, though some feel it does not compare favorably to AliExpress options. Overall, owners appreciate the Borealis Porto Covo for its distinctive dial design and wearable 39mm case size.

Seestern S450 Ocean Star

Owners widely praise the Seestern S450 Ocean Star's Yachtmaster-style case and flawless bracelet finishing, with one owner noting the ST2130 movement keeps good time. The bezel action is described as having individual notches but feeling like a friction bezel, while another owner flags the bezel and crown action as smooth with perfect alignment. Lume is a point of contention, with one source describing it as a nice cool blue with ice-white application, while others note it as weak or not matching Prospex standards, despite using BGW-9. The watch is considered a "big boy" ideal for larger wrists (19cm+), potentially too large for 17cm wrists due to its size and non-tapering bracelet. Overall, owners rate the Seestern S450 Ocean Star highly for its build quality and finishing at the price point, despite some reservations about its size and lume intensity.

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