Seiko · Presage Sharp Edged Series and Presage Cocktail Time

Seiko SPB331J1 vs Seiko SRE007J1

13 published specifications differ between these two, and 1 are identical. Every figure below is what the manufacturer states for that reference; nothing is inferred from the other watch.

What differs

Specification	Seiko Sharp Edged Series Kabuki-inspired Limited Edition, 6R35SPB331J1	Seiko Cocktail Time, 2R05, 30.3 mm, dial with diamondsSRE007J1
Case	Stainless steel with hard coating, 39.3 mm	Stainless steel, 30.3 mm
Diameter	39.3 mm	30.3 mm
Thickness	11.1 mm	10.9 mm
Lug to lug	47.2 mm	37 mm
Lug width	20 mm	14 mm
Water resistance	10 bar	5 bar
Crystal	Sapphire crystal, anti-reflective coating on inner surface	Box-shaped Hardlex
Case back	See-through and screw case back, engraved LIMITED EDITION and serial number	Screw case back
Bracelet	Bracelet length 195.0 mm, 20 mm between the lugs	14 mm between the lugs
Calibre	6R35	2R05
Power reserve	Approximately 70 hours	Approximately 40 hours
Jewels	24	21
Movement notes	Precision stated as +25 to −15 seconds per day. Stop second hand function and date display. Total weight 83.0 g. Limited edition of 2,000 pieces.	Stop second hand function and date display. Listed by Seiko as a women's model. No daily precision figure, LumiBrite line, clasp type or weight is published for this reference.

What is identical

Worth knowing as much as the differences: these are the specifications you cannot use to tell the two apart.

Movement: Automatic with manual winding

Stated for one, not the other

These rows cannot be compared, because one maker publishes the figure and the other does not. An empty cell is a gap in the manufacturer's documentation, not a gap in the watch — and not a licence to fill it in from the other column.

Dial	not stated	Set with diamonds, as listed under the reference's features
Clasp	Three-fold clasp with push button release	not stated

What the differences cost you

Each note below follows from the published figures in the tables above — what they mean for intake, for a listing, and for the handover. Nothing here estimates a price or a margin.

One of these is the harder fit

Lug to lug is 47.2 mm on the SPB331J1 against 37 mm on the SRE007J1 — a 10.2 mm difference across the wrist. Diameter is what buyers ask about; lug to lug is what decides whether a case sits flat or overhangs. Ask for a wrist measurement before shipping the SPB331J1, and put the figure in the listing rather than the diameter alone.

These reach different buyers

39.3 mm on the SPB331J1 against 30.3 mm on the SRE007J1. Diameter is a poor predictor of how a watch actually sits, but it is the field buyers filter on, so the two land in front of different people. Do not let one listing's photographs or copy stand in for the other.

Do not describe these the same way

The SRE007J1 is rated to 50 metres and the SPB331J1 to 100. A rating is a factory figure for a new watch with fresh gaskets, not a promise about a used one — but the gap still matters in writing. Describe the SRE007J1 in words a buyer can act on, and do not let a template carry the SPB331J1's language onto it.

One survives the weekend and one does not

70 hours on the SPB331J1 against 40 on the SRE007J1. Below about sixty hours a watch left off the wrist from Friday is stopped by Monday. Wind both fully at intake and confirm they reach the stated figure — a short reserve leaves a tired barrel nowhere to hide, and it is the kind of fault a buyer reports in week two.

What to check on each

SPB331J1

Photograph the engraved serial number on the case back and record it. On a numbered edition the serial is part of the object, and a buyer will ask for it before agreeing a price.
Examine the hard coating at the lug edges and around the clasp for wear through to the steel beneath. A coated case cannot be polished back, so any breakthrough is permanent and must be disclosed.
Confirm the crystal is the flat sapphire published for this reference rather than the curved sapphire used on the Prospex models, since the two are not interchangeable parts.

SRE007J1

Count the set stones against a photograph of a known-correct example and check each one is seated and unchipped. A dial with stones is the one place on a watch where a missing component can be very small and very obvious.
Read the rating as 5 bar and describe it that way. It is the lowest figure of any Seiko documented here, and it is a rating for splashes rather than swimming.
Note the box-shaped Hardlex crystal. It stands proud of the case like a box sapphire but scratches like mineral glass, so it both takes knocks and can often be polished.

Sources

Not affiliated with Seiko. Specifications are read from each manufacturer's own published documentation on the dates shown and may change; the manufacturer's current documentation governs.