Mike if you are thinking of air driven bags with 4 controls like We have in our 5C it is a 1/4" line or 3/8" would be faster up and down supply the air from the control to each set of bags. We connected the front 2 on the left together and the front 2 on the right together. Same in the rear. Then run all lines to the valves up front where you can reach them from the drivers seat. You will have two air line hookups on the back of the controls for each set of bags. So one line from bags to each control outlet, then connect the other 4 inlets together with tubing and the end of those lines into one line that will go to your supply air accessories tank. Mount your controls and I left in the leveling valves in case I ever needed them. Your done.