Spanner Wrench & Thrust Bearing Kit:?Spanner wrench tool is used to adjust vehicle height while shock stays mounted. This wrench is needed to make height adjustments. The thrust bearing kit is designed to be placed between the spring and the spring seat attached to the shock. This makes for easier adjustments since the spring seat is rotating on a bearing. This kit is recommended for easier adjustments but is not needed to complete the installation. We do not recommend adjusting height on the car without a thrust bearing kit.