Which is cheaper, the Sheffield 1A 40mm or the Seiko Prospex Sea?

At MSRP the Sheffield 1A 40mm is the cheaper of the two at $228, against $900 for the Seiko Prospex Sea — a $672 gap before any retailer discounting.

Which is bigger, the Sheffield 1A 40mm or the Seiko Prospex Sea?

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

Which has a longer power reserve, the Sheffield 1A 40mm or the Seiko Prospex Sea?

The Seiko Prospex Sea carries a 70-hour power reserve against 40 hours on the Sheffield 1A 40mm.

What movement does the Sheffield 1A 40mm run compared to the Seiko Prospex Sea?

Both watches run automatic movements — the Sheffield 1A 40mm uses the Seiko NH35 and the Seiko Prospex Sea uses the 6R35.

Side by side

Sheffield 1A 40mmvsSeiko Prospex Sea

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

Add a watch

Sheffield 1A 40mm

allsport-1-auto

MSRP $228

Seiko Prospex Sea

spb317j1

MSRP $900

At a glance

12 of 29 specs differ

Diameter

1A 40mm40mm

Prospex Sea41mm

Power Reserve

1A 40mm40h

Prospex Sea70h

Water Resistance

1A 40mm200m

Prospex Sea200m

MSRP

1A 40mm$228

Prospex Sea$900

Full specifications

Case

4 specs

Crystal & Dial

4 specs

Crystal Shape

Flat

Curved

AR Coating

Inner

Anti-reflective coating on inner surface

Dial Color

—

Black

Lume

None

LumiBrite on hands, index(es) and bezel

Movement

3 specs

Caliber

Seiko NH35

6R35

Power Reserve

40h

70h

Jewels

Pricing

1 specs

MSRP

$228

$900

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Sheffield 1A 40mmvsSeiko Prospex Sea

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