I had these on my camper shell on my last truck and will be putting them on the shell of my new truck to move my Thule racks over. Great system with a very nice fit and finish. The paint fades on the tracks after about 1 year, but whatever...it still works and doesn't rust, it just blemishes. When putting the TK1 fit kit in here, you will notice that the channel is a little narrow, so you have to go in at a 45 degree angle as you attach/insert the fit kit into these channels/rails. To me, this is a plus, because it means that if your TK1 kit ever loosens, it's not likely to come out on its own.
2005 Nissan Frontier