The Skyjacker 4" lift kit for the Jeep Wrangler YJ includes both front and rear Softride leaf springs with bushings and u-bolts with track bar brackets. A pitman arm, transfer case lowering kit, sway bar disconnects and longer shocks are required and sold separately. The Softride springs manufactured by Skyjacker use tapered leaves to yield a lower spring rate and better travel, Teflon wear pads to help reduce interleaf friction, a "bolt" style clip to reduce leaf friction and shot-peening to compress the steel and increase its tensile strength.