I've done some more reading since I posted about the bags. I think they are Air Lift 1000's. That's what it looks like from pictures I found online. Like I said earlier, you have to maintain a minimum of 5psi so the bags stay inflated inside the springs. Max psi is 35 and you fill the bags "before" you load the truck. Once the truck is loaded, you can let air out of the bags to level the ride. My bags are teed together and the valve is right next to the license plate. Some people online say to run each line separately but the instructions I read say it can be done both ways. The nut and cap on the valve are rusting so I'll need to find a stainless nut and a plastic cap for the valve. I don't want it to stain my bumper.