Which is cheaper, the Sangin Instruments Hydra II or the Seiko Prospex Sea Save the Ocean Special Edition?

At MSRP the Seiko Prospex Sea Save the Ocean Special Edition is the cheaper of the two at $625, against $1,795 for the Sangin Instruments Hydra II — a $1,170 gap before any retailer discounting.

Which is bigger, the Sangin Instruments Hydra II or the Seiko Prospex Sea Save the Ocean Special Edition?

The Seiko Prospex Sea Save the Ocean Special Edition wears larger at 45mm versus 43mm for the Sangin Instruments Hydra II — a 2mm difference across the dial.

Which has better water resistance, the Sangin Instruments Hydra II or the Seiko Prospex Sea Save the Ocean Special Edition?

The Sangin Instruments Hydra II is rated to 300m versus 200m for the Seiko Prospex Sea Save the Ocean Special Edition.

What movement does the Sangin Instruments Hydra II run compared to the Seiko Prospex Sea Save the Ocean Special Edition?

Both watches run automatic movements — the Sangin Instruments Hydra II uses the La Joux-Perret G100 and the Seiko Prospex Sea Save the Ocean Special Edition uses the Seiko 4R36.

Side by side

Sangin Instruments Hydra IIvsSeiko Prospex Sea Save the Ocean Special Edition

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

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Sangin Instruments Hydra II

MSRP $1,795

See the full Hydra II

Seiko Prospex Sea Save the Ocean Special Edition

MSRP $625

See the full Prospex Sea Save the Ocean Special Edition

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Buy from Seiko ↗

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At a glance

15 of 29 specs differ

Diameter

Hydra II43mm

Prospex Sea Save the Ocean Special Edition45mm

Power Reserve

Hydra II—

Prospex Sea Save the Ocean Special Edition41h

Water Resistance

Hydra II300m

Prospex Sea Save the Ocean Special Edition200m

MSRP

Hydra II$1,795

Prospex Sea Save the Ocean Special Edition$625

Full specifications

Case

7 specs

Crystal & Dial

4 specs

Crystal

—

Sapphire

AR Coating

—

Anti-reflective coating on inner surface

Dial Color

Polar White

—

Lume

None

LumiBrite on hands, index(es) and bezel

Movement

3 specs

Caliber

La Joux-Perret G100

Seiko 4R36

Power Reserve

41h

Jewels

Pricing

1 specs

MSRP

$1,795

$625

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