Which is cheaper, the Casio GST-B100 or the Seiko Prospex SPEEDTIMER?

At MSRP the Casio GST-B100 is the cheaper of the two at $385, against $725 for the Seiko Prospex SPEEDTIMER — a $340 gap before any retailer discounting.

Which is bigger, the Casio GST-B100 or the Seiko Prospex SPEEDTIMER?

The Casio GST-B100 wears larger at 53.8mm versus 39mm for the Seiko Prospex SPEEDTIMER — a 14.8mm difference across the dial.

Which has better water resistance, the Casio GST-B100 or the Seiko Prospex SPEEDTIMER?

The Casio GST-B100 is rated to 200m versus 10m for the Seiko Prospex SPEEDTIMER.

Side by side

Casio GST-B100vsSeiko Prospex SPEEDTIMER

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

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Casio GST-B100

GST-B100

MSRP $385

See the full GST-B100

Seiko Prospex SPEEDTIMER

MSRP $725

See the full Prospex SPEEDTIMER

At a glance

16 of 29 specs differ

Diameter

GST-B10053.8mm

Prospex SPEEDTIMER39mm

Power Reserve

GST-B100—

Prospex SPEEDTIMER—

Water Resistance

GST-B100200m

Prospex SPEEDTIMER100m

MSRP

GST-B100$385

Prospex SPEEDTIMER$725

Full specifications

Case

8 specs

Crystal & Dial

5 specs

Crystal

Mineral

Sapphire

Crystal Shape

—

Curved

AR Coating

Anti-reflective coating on inner surface

Dial Color

Black

—

Lume

None

LumiBrite on hands and index(es)

Movement

2 specs

Caliber

—

V192

Power Reserve

—

Pricing

1 specs

MSRP

$385

$725

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Casio GST-B100vsSeiko Prospex SPEEDTIMER

At a glance

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