Seiko SRE007J1: specifications and what to check

Stones are the only components you can count

Seiko lists dial with diamond(s) among this reference's features, and that one line adds an inspection step no other watch documented here requires.

Set stones can be missing, and a missing stone is simultaneously tiny and unmissable. An empty setting catches the light differently from a filled one, and once a buyer notices it they will not see anything else.

So count them. Find a reference image of a correct example — the manufacturer's own product photography is the right source — and count the settings on the watch in front of you against it. Then look at each one under a loupe for:

• A stone sitting proud or tilted, which means the setting has opened
• Chipped girdles, particularly on small stones near the edge of the dial
• Prongs or bezel settings that have been pushed, usually from a clumsy crystal change

None of this is expensive to correct in absolute terms, but all of it has to be disclosed, and a photograph taken straight on under flat light will hide every bit of it. Shoot the dial at an angle with a raking light so the settings throw shadows.

Five bar is the lowest rating here

The water resistance is 5 bar.

That is below the 10 bar of the dress and sports models here and far below the diver's ratings; only a handful of dress references, at 3 bar, go lower.

Five bar is a splash rating. Rain, hand washing, an accidental soaking. Not swimming, not showering, not washing up. On a watch that will plausibly be worn every day by someone who is not thinking about it, that limitation belongs in the listing in plain words rather than as a number in a table.

A box crystal made of mineral glass

The crystal is specified as box-shaped Hardlex, which combines two properties that usually come separately.

Box-shaped means it stands above the case in a squared profile — the same geometry as the box sapphire on the Grand Seiko and Prospex references here. That shape is exposed: it is the highest point on the watch and it meets door frames first.

Hardlex means it is Seiko's hardened mineral glass, not sapphire. It scratches in ordinary use, and it can frequently be polished.

So you get the vulnerability of a raised crystal and the forgiveness of a polishable one at the same time. A marked example is a cheap refresh; a cracked one is a shaped replacement.

Describe it as Hardlex. A buyer who is told sapphire and later discovers otherwise has a fair grievance.

Small, narrow, and thinly documented

Published: 30.3 mm in diameter, 10.9 mm thick, 37.0 mm lug to lug, with 14 mm between the lugs. The movement is the 2R05: 21 jewels, approximately 40 hours, automatic with manual winding, stop seconds and a date.

Two practical notes.

Fourteen millimetres is narrow. Strap choice at that width is a fraction of what is available at 20 or 22, and a buyer planning to change the band should hear that before they buy rather than after.

Seiko publishes less here than elsewhere. There is no precision figure, no LumiBrite line, no clasp type and no weight on this page — all of which the Prospex references carry.

Those are gaps in the documentation, and the correct way to handle them is to say so. Describe what the maker states; where it states nothing, report your own observation and label it as yours. Borrowing the +25 to −15 seconds per day quoted for the 6R calibres and attaching it to a 2R05 is a claim nobody can support.