Which is cheaper, the Borealis Watch Co. Sea Storm MK2 GMT or the Seiko Prospex SPEEDTIMER Mechanical?

At MSRP the Borealis Watch Co. Sea Storm MK2 GMT is the cheaper of the two at $415, against $995 for the Seiko Prospex SPEEDTIMER Mechanical — a $580 gap before any retailer discounting.

Which is bigger, the Borealis Watch Co. Sea Storm MK2 GMT or the Seiko Prospex SPEEDTIMER Mechanical?

The Borealis Watch Co. Sea Storm MK2 GMT wears larger at 41.50mm versus 39.5mm for the Seiko Prospex SPEEDTIMER Mechanical — a 2mm difference across the dial.

Which has better water resistance, the Borealis Watch Co. Sea Storm MK2 GMT or the Seiko Prospex SPEEDTIMER Mechanical?

The Borealis Watch Co. Sea Storm MK2 GMT is rated to 300m versus 20m for the Seiko Prospex SPEEDTIMER Mechanical.

Which has a longer power reserve, the Borealis Watch Co. Sea Storm MK2 GMT or the Seiko Prospex SPEEDTIMER Mechanical?

The Seiko Prospex SPEEDTIMER Mechanical carries a 72-hour power reserve against 40 hours on the Borealis Watch Co. Sea Storm MK2 GMT.

What movement does the Borealis Watch Co. Sea Storm MK2 GMT run compared to the Seiko Prospex SPEEDTIMER Mechanical?

Both watches run automatic movements — the Borealis Watch Co. Sea Storm MK2 GMT uses the NH34 and the Seiko Prospex SPEEDTIMER Mechanical uses the 6R55.

Side by side

Borealis Watch Co. Sea Storm MK2 GMTvsSeiko Prospex SPEEDTIMER Mechanical

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

Borealis Watch Co.Sea Storm MK2 GMT

borealis-sea-storm-mk2-gmt-version-aa

MSRP $415

Seiko Prospex SPEEDTIMER Mechanical

spb513j1

MSRP $995

At a glance

13 of 29 specs differ

Diameter

Sea Storm MK2 GMT41.50mm

Prospex SPEEDTIMER Mechanical39.5mm

Power Reserve

Sea Storm MK2 GMT40h

Prospex SPEEDTIMER Mechanical72h

Water Resistance

Sea Storm MK2 GMT300m

Prospex SPEEDTIMER Mechanical200m

MSRP

Sea Storm MK2 GMT$415

Prospex SPEEDTIMER Mechanical$995

Full specifications

Case

6 specs

Crystal & Dial

3 specs

Crystal Shape

Flat

Curved

AR Coating

Inner

Anti-reflective coating on inner surface

Lume

BGW9

LumiBrite on hands and index(es)

Movement

3 specs

Caliber

NH34

6R55

Power Reserve

40h

72h

Jewels

Pricing

1 specs

MSRP

$415

$995

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