“I personally love the concept of electronic boards connected in “slots” (vertically attached to a horizontal board), like most industrial-grade PLC’s or even our desktop’s expansion cards (video, sound memory): it saves a lot of space and adds more functions to the system, all at once!. This is yet another Arduino compatible stuff, but with an interesting difference: it is meant to be vertically mounted to a breadboard or PCB, different from the Arduinos we see out there (that you attach horizontally to the breadboard or PCB). “