![Image](http://image.noelshack.com/fichiers/2016/05/1454629153-sans-titre.png)
With this system, if you take only the red or blue side of the belt in your inventory (or taken by an inserter), the yellow input will be balancing. It will take equally the two side of the belt. Try it, i'm really bad in english and i don't know how to explain it in a better way! I like to put this system at the end of my furnace for example, very good balancing!
Edit : A little bit compact.
![Image](http://image.noelshack.com/fichiers/2016/05/1454629840-sans-titre.png)