Below this the thing is two OTTO components prototypes. Element smart They can be very similar, but the main just one is hand-wired, lasercut, and utilizes arduino pro micros for dealing with the keys/encoders. The second one is 3D printed, uses a PCB with onboard microcontroler and so on. to http://caidenbtkbs.articlesblogger.com/5532849/not-known-factual-statements-about-otto