Traxxas package of replacement spring pre-load spacers that comes with the Stampede and Rustler trucks along with the black long shocks and black XX-long shocks. Made of a black plastic/nylon material. Used to help pre-load the shock springs. This is installed on the top of the shock springs. Enough for one pair of shocks. This package includes two spacers 1mm thick, two spacers 2mm thick, two spacers 3mm thick and two spacers that are 4mm thick. Also fits shocks with a 13.5mm outside diameter body..