Hi, yesterday I got a JK 1680 from HK. I had one some years ago and I was keeping a Sternkreuz glass to replace the one that comes with the watch (the lens magnifies too much).
To my surprise I found the glass was glued to the case. I had to dismantle everything and use a pipe wrench to get a grip and remove it. The crown seems also smaller (thinner) than the past.
Do we have comparison pics for these JK watches over the years? I got it from Marvellousreplica.
In the pic my gen 1675 and JK 1680.