Which is cheaper, the Seiko Prospex SPEEDTIMER or the Sunrex 321?

At MSRP the Sunrex 321 is the cheaper of the two at $600, against $750 for the Seiko Prospex SPEEDTIMER — a $150 gap before any retailer discounting.

Which is bigger, the Seiko Prospex SPEEDTIMER or the Sunrex 321?

The Seiko Prospex SPEEDTIMER wears larger at 41.4mm versus 38.6mm for the Sunrex 321 — a 2.8mm difference across the dial.

Which has better water resistance, the Seiko Prospex SPEEDTIMER or the Sunrex 321?

The Sunrex 321 is rated to 100m versus 10m for the Seiko Prospex SPEEDTIMER.

What movement does the Seiko Prospex SPEEDTIMER run compared to the Sunrex 321?

The Seiko Prospex SPEEDTIMER runs a quartz caliber (V192), while the Sunrex 321 runs a solar (Epson VS76A).

Side by side

Seiko Prospex SPEEDTIMERvsSunrex 321

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

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Seiko Prospex SPEEDTIMER

ssc911

MSRP $750

Sunrex 321

321-racer

MSRP $600

At a glance

12 of 29 specs differ

Diameter

Prospex SPEEDTIMER41.4mm

32138.6mm

Power Reserve

Prospex SPEEDTIMER40h

32140h

Water Resistance

Prospex SPEEDTIMER100m

321100m

MSRP

Prospex SPEEDTIMER$750

321$600

Full specifications

Case

6 specs

Crystal & Dial

3 specs

Crystal Shape

Curved

Flat

AR Coating

Anti-reflective coating on inner surface

Yes

Lume

LumiBrite on hands and index(es)

None

Movement

2 specs

Caliber

V192

Epson VS76A

Type

Quartz

Solar

Pricing

1 specs

MSRP

$750

$600

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Seiko Prospex SPEEDTIMERvsSunrex 321

At a glance

Full specifications

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