Output:
-1 compressed blue belt of processing units.
Inputs:
-12 belts of green circuits
-12 belts of green/red mixed circuits
by Unknown Author · updated 7/25/2017 · 10

Originally shared on the public FactorioPrints / Factorio School archive (factorioprints.com · factorio.school). Authorship preserved from the public catalog.
Output:
-1 compressed blue belt of processing units.
Inputs:
-12 belts of green circuits
-12 belts of green/red mixed circuits