Springs are preset to reduce settling and to improve life. Leaf ends are trimmed to reduce friction and improve stress distribution. Individual leaves are shot-peened to reduce stress and improve fatigue life. Covered by Rancho's limited lifetime warranty.
Very happy with this, however I did assume these leaf springs worked with stock bushings and they do not. There is a bushing kit that is separate. Also my old bolts had to be cut out so I wished I had ordered those as well, they are hard to find.