Turtle

Hacking seconds separates a 6306 from a 6309 without opening the case

Pull the crown to the time-setting position. The 6306A stops the seconds hand; the 6309A does not. Combined with the Kanji day wheel, this is a decisive, non-invasive check — and it is the check that catches the common misrepresentation, which is an export 6309 sold as the rarer JDM 6306.

The Kanji day wheel is expected, and its absence is a question

A 6306 was supplied with a Japanese-market day wheel showing Kanji alongside English. An English-only wheel in a 6306 case usually indicates a service replacement, since Seiko service centres outside Japan fitted the parts they stocked. Record it as a service change; it does not make the watch an export model, and it does not make it inauthentic.