For ultimate control during jumping and bumping, Traxxas Big Bore shocks are the perfect addition to your Traxxas model. The hard-anodized aluminum housing, PTFE-coated shock shafts, and titanium-nitride-coated rods provide incredible durability and nearly frictionless operation for ultra-smooth damping and long-lasting performance. Progressive rate springs for the 2WD Slash are included; for the best performance with Rustler, Bandit, Stampede, Craniac, and Skully, install the springs that come with your model.