Summary

These are Arduino Mega case options. You can learn more about them and how to use them here....

http://1fatgmc.com/RailRoad/3D-Printer-2/page-50.html

Prints were printed with an Ender 3 Pro using Cura set on 'Standard Quality' in the 'Profile' setting and with a stock .4 nozzle.

More on other items of designed here ....

http://1fatgmc.com/RailRoad/3D-Printer/3D-Printer-Index.html