These direct - fit front upper control arms add strength, on - car adjustability and articulation flexibility to your stock - height or 'lifted' suspension Wrangler. They feature SPC's xAxis sealed flex joints mounted in forged rings at the frame ends to provide bind - free 'twist' between the frame and axle during off - road articulation. The dual - threaded adjuster and jam nuts make casterpinion angle adjustments quick and easy without the need to disconnect the arms or mess with cams and slotted hole knock - outs. Main tube is 316 wall DOM steel for 'overkill' strength to handle large tires, low gearing, and big horsepower. California Residents WARNING