Importing and Exporting - badasintended/slotlink GitHub Wiki
As of 1.2.6, transfer cables are disabled by default. you need to enable it on the options.
With release 1.0, slotlink added two more cable types, which are import and export cable!
As the name suggests, it used to transfer items from or into the network.
Crafting Recipe
The recipe for import cable is

and you can convert it back and forth between import & export

Note to Server Owners
Transferring items are proven to be causing some lag on server, which actually makes sense since it needs to loop through big systems every second.
If you don't want to deal with it, you can disable the import/export cable recipe altogether.