RockJock's Johnny Joint® front upper control arms for the 1997-2006 Jeep TJ Wrangler and LJ Unlimited, as well as all years of XJ Cherokee, MJ Comanche and ZJ Grand Cherokee vehicles provides length adjustability allowing pinion angle and caster angle to be adjusted. The adjustable feature of our arms allows your vehicle to be upgraded to different lift amounts without having to replace the control arms in the future. Arms are made from 1" x .156" wall D.O.M. tubing, are powder coated semi-gloss black, and come with zerk fitted grade 8 mounting bolts. To allow complete unrestricted movement, the Johnny Joint® at the frame end of the arm and the housing end features a fork for mounting to the front housing bushing. You can replace these stock front end bushings with our CE-9102K Johnny Joint® front end housing conversion kit. NOTE: Some stock frontend housings feature 10mm upper control arm bolts, where others are already 7/16". If your frontend housing features the 10mm, you will have to drill these holes out to 7/16".