Which is cheaper, the Casio GST-B400 or the Seiko Prospex Rotocall?

At MSRP the Casio GST-B400 is the cheaper of the two at $350, against $550 for the Seiko Prospex Rotocall — a $200 gap before any retailer discounting.

Which is bigger, the Casio GST-B400 or the Seiko Prospex Rotocall?

The Casio GST-B400 wears larger at 49.6mm versus 37mm for the Seiko Prospex Rotocall — a 12.6mm difference across the dial.

Which has better water resistance, the Casio GST-B400 or the Seiko Prospex Rotocall?

The Casio GST-B400 is rated to 200m versus 10m for the Seiko Prospex Rotocall.

Side by side

Casio GST-B400vsSeiko Prospex Rotocall

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

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Casio GST-B400

GST-B400

MSRP $350

See the full GST-B400

Seiko Prospex Rotocall

MSRP $550

See the full Prospex Rotocall

At a glance

13 of 29 specs differ

Diameter

GST-B40049.6mm

Prospex Rotocall37mm

Power Reserve

GST-B400—

Prospex Rotocall—

Water Resistance

GST-B400200m

Prospex Rotocall100m

MSRP

GST-B400$350

Prospex Rotocall$550

Full specifications

Case

7 specs

Diameter

49.6mm

37mm

Thickness

12.9mm

10.6mm

Lug-to-Lug

46.6mm

43.5mm

Lug Width

—

20mm

Material

Resin / Stainless steel

Stainless Steel

Finish

—

Water Resistance

200m

100m

Crystal & Dial

3 specs

Crystal

Mineral

Hardlex

AR Coating

—

Dial Color

Black

—

Movement

2 specs

Caliber

—

A824

Power Reserve

—

Pricing

1 specs

MSRP

$350

$550

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Casio GST-B400vsSeiko Prospex Rotocall

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