Flexible Coupler (3mm to 6.35mm) load ATmega16U2 instead of the 8U2

ATmega16U2 instead of the 8U2 found

LM2575T-12  (LM2575 Step-Down 12V Voltage Regulator)

6VDC supply range

allowing resets when shields are connected

It is designed to be used with a magnet to sense the rotating speed (incremental position) of a ferrous tooth-wheel

Flexible Coupler (3mm to 6.35mm) load ATmega16U2 instead of the 8U2Connect motor shaft to anything else with a set screw coupler. These couplers are made of machined aluminum and have a spiral cut that makes them slightly flexible so they can be fit to two shafts even if they are not perfectly co linear and will help reduce bending effects. The way they are cut, create a spring effect in the X Y & Z linear axis but not in the rotational axis. That means that you will not get increased backlash so they're suitable for