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 $1,100 for the Seiko Prospex Sea — a $872 gap before any retailer discounting.

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

The Seiko Prospex Sea wears larger at 41.3mm versus 40mm for the Sheffield 1A 40mm — a 1.3mm difference across the dial.

Which has better water resistance, the Sheffield 1A 40mm or the Seiko Prospex Sea?

The Seiko Prospex Sea is rated to 300m versus 200m for the Sheffield 1A 40mm.

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

The Seiko Prospex Sea carries a 72-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 6R55.

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

spb481j1

MSRP $1,100

At a glance

12 of 29 specs differ

Diameter

1A 40mm40mm

Prospex Sea41.3mm

Power Reserve

1A 40mm40h

Prospex Sea72h

Water Resistance

1A 40mm200m

Prospex Sea300m

MSRP

1A 40mm$228

Prospex Sea$1,100

Full specifications

Case

5 specs

Crystal & Dial

3 specs

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

6R55

Power Reserve

40h

72h

Jewels

Pricing

1 specs

MSRP

$228

$1,100

Keep exploring

More watches worth a look

Matched to the watches above on size, movement, style and price — microbrands first. Open any one to dig in.

Filippo Loreti Watchesmicro

Joker

Follow this matchup

Get a note when Sheffield 1A 40mm vs Seiko Prospex Sea gets more votes, a community discussion, or a price drop. No account needed.

Adjacent matchups

People also compared

Comparisons nearby in the catalog — alternatives to the watches above paired against the matchup.

Sheffield 1A SCR II BluevsSeiko Prospex Sea Sheffield 1AvsSeiko Prospex Sea Sheffield 1A diver ~40mm 3-hand, Arabic numerals (12/3/6/9), no datevsSeiko Prospex Sea Filippo Loreti Watches The Joker MadnessvsSeiko Prospex Sea Borealis Watch Co. Estoril 300 GMTvsSheffield 1A 40mm Borealis Watch Co. JamantavsSheffield 1A 40mm

Edit this comparison Add another watch Explore more 39–43mm watches

Sheffield 1A 40mmvsSeiko Prospex Sea

At a glance

Full specifications

More watches worth a look

The Joker Madness

Estoril 300 GMT

Aquadiver

Jamanta

COURG: Zero-Hour

COURG: Minimalist

Pathfinder

Daibāzu: Cookie Monster SUB

Follow this matchup

People also compared