Hopper ducts is a mod that adds two things to the game, filters and pipes. The pipes will allow us to connect certain hoppers to others, creating object distribution systems, while the filters will allow us to filter and define which objects we want to pass through the hopper and which not.

This will allow us to create more efficient and elegant distribution systems than creating a network of hoppers on top of each other, which the hoppers in the game allow us to do today. In this way, we can physically extend a filtering and distribution system, in a simple, efficient and more elegant way.