The All Balls Racing IRS Knuckle Kits contain everything required to rebuild the rear knuckle. Needle bearing shafts are 52100 hardened and precision ground bearing steel. Self lubricating Acetal nylon bushings for better wear and performance. All metal bushings are case hardened and plated to prevent wear and corrosion. Note: Kit contents will vary by fitment and are subject to change. Kit Includes: 4 Delrin bushing(s). 2 needle bearing shaft(s). 4 seal(s).