Which is cheaper, the Sheffield 1A or the Seiko Prospex Sea?

At MSRP the Sheffield 1A is the cheaper of the two at $223, against $900 for the Seiko Prospex Sea — a $677 gap before any retailer discounting.

Which is bigger, the Sheffield 1A or the Seiko Prospex Sea?

The Seiko Prospex Sea wears larger at 41mm versus 40mm for the Sheffield 1A — a 1mm difference across the dial.

What movement does the Sheffield 1A run compared to the Seiko Prospex Sea?

Both watches run automatic movements — the Sheffield 1A uses the Seiko NH35A and the Seiko Prospex Sea uses the 6R35.

Side by side

Sheffield 1AvsSeiko Prospex Sea

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

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Sheffield 1A

diver-1a-40mm-white

MSRP $223

Seiko Prospex Sea

spb317j1

MSRP $900

At a glance

11 of 29 specs differ

Diameter

1A40mm

Prospex Sea41mm

Power Reserve

1A—

Prospex Sea70h

Water Resistance

1A200m

Prospex Sea200m

MSRP

1A$223

Prospex Sea$900

Full specifications

Case

3 specs

Diameter

40mm

41mm

Thickness

12.8mm

12.3mm

Lug-to-Lug

46mm

46.9mm

Crystal & Dial

4 specs

Crystal Shape

Flat

Curved

AR Coating

Inner

Anti-reflective coating on inner surface

Dial Color

White/Blue

Black

Lume

Swiss blue lume

LumiBrite on hands, index(es) and bezel

Movement

3 specs

Caliber

Seiko NH35A

6R35

Power Reserve

—

70h

Jewels

Pricing

1 specs

MSRP

$223

$900

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Sheffield 1AvsSeiko Prospex Sea

At a glance

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