Macintosh Portable PSI RAM plus ??? Card

[Sideburn]

Hey guys, I’ve acquired this RAM plus more expansion card for a portable. It’s showing 5MB in the finder.

but there’s 4 switches and two cards sandwiched together. Any idea what this card is and what all it can do?

 

[ClassicHasClass]

Those all look like RAM to me.

 

[Sideburn]

I wonder what all the switch settings are

 

[moldy]

https://68kmla.org/bb/index.php?threads/psi-cards-for-macintosh-portable.27787/ maybe this thread on 68kmla can be helpful for you, it has a vague description what the switches are for