A vintage 1970 SMITH-CORONA MARCHANT Electronic Calculator.

This is a model called the " MARCHANT I RX ".  I could find no information online about this particular model which I found odd. It could be some sort of prototype I suppose and the sticker on the bottom perhaps is an indicator of that. It reads :

" MFG. ENGINEERING PROTOTYPE PARTS   J.C. CLARK "

After doing a bit of research I found out that at SCM there worked a John C. Clark who invented Dual Key depression for decimal point selection for SCM in 1969. Also, the estate I bought it from was in Oakland, CA and that is where their manufacturing plant was so who knows? 

It appears to be the same design as the MARCHANT I and comes with the manual for that model.

Cosmetically it is in quite fine condition. It didn't come with the charger cord so it is being offered in "as found" untested condition. Any repairs or refurbishment that might be needed I shall leave to the new owner.