This is the optional ST Racing Aluminum Rear Shock Set in Bluefor the Traxxas 1/10 scaleNitro Slash, Slash 2wd, Slash 4x4, Stampede 4x4, Bandit, Rustler, Monster Jam.FEATURESCNC machined aluminum bodiesPreload collars with O-ring installed keeps adjustments in placeLower shock caps keep the shock straight and flex freeduring suspension operation and heavy compressionINCLUDESTwo each, Bodies, Preload Collars with O-Rings, and Lower Shock Caps