The top half of the case for Auto-Reflex P has extra room for the installed light meter.
Compared to the Auto-Reflex with a inboard meter, I noticed at least six superficial differences between the sibling models, not including the differences on the upper case as I mentioned above and a tiny one on the lens coming with the Auto-reflex P.
The slid-on light meter is powered by a cell battery. The lens sold with Auto-Reflex P has a yellow dot after f16 on the aperture ring. This is the EE or AE gear on other Koinca AR lens/zoom. Since there is no EE/AE function on Auto-Reflex P body, the lens is only 'yellow dotted', not marked otherwise.
The light meter seems complicated. I neither have nor find a manual for the meter. If you as my reader happen to have a copy of the manual, I hope you can scan and post it online. Instead, I used a Petri Shoe-mount light meter when I shot with my Auto-Reflex P.
Also saw a black version of Auto-Reflex P as shown in the following image.
An identical JDM-version of Konica Autorex P was sold in Japan. Similarly, Revue SP marketed in Germany and Europe.
Today, when I prepared this post, I found that several websites for Koinca camera/lens have been shut down. This is not good for the users of Konica film cameras although there are not many such people out there. I hope Konica-Minolta, Pentax and Ricoh, I mean the camera companies, also set up their official camera museums online, as Canon does. I believe, this is not only for commercial reason, but also for their long-time users, education, technology history and more.