[pwg]

HP produced the HP-16C for programmers a long time ago:

https://en.wikipedia.org/wiki/HP-16C

Swiss Micro seems to be producing clones:

https://www.amazon.com/SwissMicros-DM16L/dp/B01DYTVZF2

[Tor3]

I have one, bought it new many decades ago. If the SwissMicro clones have as good keys as the old HP originals then I wouldn't hesitate buying one of those if you're interested in a 16C.

[fbdab103]

I know a guy who keeps one of these on his desk today. Thing must be 20+ years old. He claims it is the only calculator he can use now.