Which is cheaper, the Sangin Instruments Hydra II or the Seiko Prospex Sea?

At MSRP the Seiko Prospex Sea is the cheaper of the two at $900, against $1,795 for the Sangin Instruments Hydra II — a $895 gap before any retailer discounting.

Which is bigger, the Sangin Instruments Hydra II or the Seiko Prospex Sea?

The Sangin Instruments Hydra II wears larger at 43mm versus 41mm for the Seiko Prospex Sea — a 2mm difference across the dial.

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

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

What movement does the Sangin Instruments Hydra II run compared to the Seiko Prospex Sea?

Both watches run automatic movements — the Sangin Instruments Hydra II uses the La Joux-Perret G100 and the Seiko Prospex Sea uses the Seiko 6R35.

Side by side

Sangin Instruments Hydra IIvsSeiko Prospex Sea

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

MSRP $900

See the full Prospex Sea

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At a glance

16 of 29 specs differ

Diameter

Hydra II43mm

Prospex Sea41mm

Power Reserve

Hydra II—

Prospex Sea70h

Water Resistance

Hydra II300m

Prospex Sea200m

MSRP

Hydra II$1,795

Prospex Sea$900

Full specifications

Case

7 specs

Crystal & Dial

5 specs

Crystal

—

Sapphire

Crystal Shape

—

Curved

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 6R35

Power Reserve

70h

Jewels

Pricing

1 specs

MSRP

$1,795

$900

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Sangin Instruments Hydra IIvsSeiko Prospex Sea

At a glance

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