Originally shared on the public FactorioPrints / Factorio School archive (factorioprints.com · factorio.school). Authorship preserved from the public catalog.
Single lane balancer (5x3). Makes sure your lopsided ugly lane turns into a perfectly balanced lane.
I use them everywhere so machines on both sides always keep working instead of waiting. Also since it starts with a splitter, you can easily merge two lanes into one balanced lane if needed.