The Arduino Mega 2560 is a microcontroller board based on the ATmega2560.
Arduino Uno is a microcontroller board based on the ATmega328P.
GRBL Compatible CNC Uno Shield and Expansion Board for 3D Printer
Arduino Nano CNC Shield V4 3D Printer Stepper Expansion Board
MKS Gen Integrated V1.4 PCB
RepRap Arduino Mega Pololu Shield for Arduino MEGA 2560 controller.